Air Spring Replacement

Photo: Front right air spring on author's 4.0SE, shown with wheel and wheel arch liner removed.

The Air springs on late model Range Rovers usually need replacing before a coil spring would sag significantly -- a cause for much complaining among Range Rover owners, especially in the early days when the "Genuine" replacements were extremely expensive (close to $US300 each) and in short supply. Nowadays inexpensive replacements have become available from aftermarket suppliers. The replacement procedure is no harder than replacing a coil, and no spring compressor is needed. In my experience it takes about an hour without any practice. Ron Beckett and I recommend replacing the bags if they are leaking at all, as the long term benefit in terms of saving the (expensive) compressor alone are probably worth it. (If you don't have a new airbag available, you can try cleaning the pistons as described at this link).

I would like to gratefully acknowledge valuable input and photos for this page from Ron Beckett, Michael Azzariti, and Kevin Kelly who have all performed these operations themselves. Their advice is supplemented by my own experiences of air spring replacement in the shop as well as in the field.

Cautionary Note: The EAS system uses air at very high pressure -- 10 bar or 150 psi. Be careful when doing any operation on it; according to the shop manual the air should be removed from the system before repairs are carried out. See notes under "Depressurizing the System". If you decide to proceed without depressurizing, do so at your own risk!!

Parts Availability
The availability of parts for this operation was transformed in 2003-2005. Whereas the genuine air springs used to cost nearly $300 each, there are now new suppliers and costs are in the $100-200 range. The pioneering innovator in the US is Arnott Industries, a long-established air suspension company whose owner drives a Range Rover. Arnott provides replacement air springs for about the same cost as a coil spring. The bellows only is US$91 for the front (Arnott #1E06), $107 for the rear (Arnott #1E06A -- about 2 inches longer) on both Classic and 4.0/4.6. The complete spring assembly for the 4.0/4.6 is only $107 (front) and $171 (rear). It is so much easier to replace the whole spring, and these prices are so low, that I now prefer to carry complete ones as spares.

Arnott has not been satisfied with simply providing look-alike replacements; they have spent considerable effort improving on the originals. They also sell a 2nd generation spring designed for extra durability, with the loose stock bellows end connections replaced by steel crimps. They have now (September 2005) produced a revolutionary Generation III design, similar to those used in the Mk III RR. These give both a softer ride off road and a firmer handling on the freeway, with 2-3 inches more travel to boot! (See on & off road test of these springs). Amazingly for air suspension parts, all Arnott air springs and bellows carry a lifetime warranty!! Arnott have kindly agreed to support this website, so please mention RangeRovers.net if you buy from them. They also have good illustrated instructions on their site for replacing the springs -- see http://arnottindustries.com/manuals/index.asp.

If you just want to replace the rubber bladders (you can re-use the top and bottom pistons of the spring), an excellent low cost source for the OEM Dunlop ones is Airbag Man in Australia (who ship worldwide). Their export price is about $80 plus shipping. (Their internal Australian prices are higher -- see below -- due to taxes).

Another US manufacturer, Strutmasters, which is primarily into coil spring conversions, now supplies both Classic and 4.0/4.6 Range Rover air spring bellows for $79 (front) or $95 (rear). What is even more amazing, they come with a lifetime warranty!! They have kindly agreed to help support this website, so if you order from them please tell them you saw their info on RangeRovers.net!

If you live in Australia, the official Arnott importer only brings the whole air spring assembly in at A$415 each (vs. A$660 for the official LR product). US$89 = A$137 - so even with shipping, customs duty and tax, it is probably cheaper to import just the bladders yourself. I am not sure if there is a Strutmasters importer in Australia yet. Or, get the OEM Dunlop bladders for about the same cost from Airbag Man in Brisbane.

If you are on a real budget you can keep an eye on eBay and pick up some used air springs (and other air suspension components) for next to nothing from a P38 owner who has made the switch to coil springs. Click here for a direct link to eBay "Range Rover air springs" search results. Over the past couple years Kevin Kelly has noticed that the price of used air springs is occasionally as low as $25 each.

You don't want the suspension to be adjusting itself up and down while you work on the vehicle. Classic air sprung models have a disable switch under the seat. On the P38, no such switch is provided, but leaving the tailgate open effectively freezes the suspension. It is wise to leave a door open as well, in case one or the other accidentally gets closed. For an extra measure of safety you can unplug the air suspension delay timer, a small black box that looks like a large relay under the left front seat (see photo at right). On the P38, removing Fuse 44 or 17 should also work.

The manual advises depressurizing the system before replacing springs, but their procedure for doing so requires the Test Book! We lesser mortals without such facilities simply skip this step (do so at your own risk of course). If you are in the field with a blown air spring, it will already be depressurized anyhow. If it is not blown and still has air in it, you can partly depressurize it by jacking up the chassis so the spring is well extended. If you want to depressurize the air tank, you can SLOWLY unscrew the drain plug -- it has a notch in the threads so when partly undone it lets the air escape without firing the plug out like a bullet.

As Dennis Altman points out, an alternative method is to de-pressurize the system using jumpers. To do this, access the main EAS ECU connector under the front of the driver's seat -- see the section on Manual EAS Valve Activation. Just connect all the valves (pin 9,10,11, 26, 27 and 28 on the she'll settle down nicely, and dump the tank for you.

Air Spring Replacement (Classic)

Replacing an air spring is no more difficult than replacing a coil spring. Michael Azzariti was surprised how easy changing a front air spring was on his 95 RR LWB, and offers the following details, which differ from those in the manual (the official procedure involves depressurizing the system), so use at your own risk. The procedure for a P38 is very similar, the main difference being the means of disabling the suspension and the type of attachments holding the spring in place. Details of the P38 procedure are given in the section below on "P38 Air Spring Replacement".

Disabling the Suspension
Michael started by setting the suspension to the high height, then turning the system off with the under seat switch.

Jacking up the Vehicle
Then, "I jacked up the front axle and put a stand under it on the side I was working on. I then disconnected the negative side on the battery. I then put my floor jack under the frame on the side I was working on. I chose the front radius arm ear, and lifted the frame just enough to take the weight of the body off the spring. I then removed the tire. So I had the axle held by the jack stand, and the frame/body by the jack. This is a bit dicey, make sure you are on a level surface and have set the parking brake and are in gear. If you are not positive, absolutely, of your jack, back it up with another stand under the frame!

Disconnecting the Air Line
Michael then disconnected the air line from the reusable fitting at the top of the spring. To release this fitting, press the brass ring down and pull on the hose. If there is pressure in the spring it will pop out with a hiss. Michael released the fitting by taking a 5/16" open end wrench, which had a wide enough opening to slip over the hose, and rested it on the brass ring and gave it gentle tap with a mallet and the fitting released. Carefully slide the hose out and cover it with a piece of tape to prevent any dirt getting in to the airline.

Remove Retaining Clips
With a large flat blade screw driver, Michael was able to push the two retaining clips off the top and bottom. Wear safety glasses as they tend to fly! Find those little clips as you may need them again as spares. The two on the top of Michael's spring were rusted into a brittle mass that had to be removed by scraping with the screwdriver. The bottom retaining clips were fine.

Replacement with New Parts
"I had purchased a set of front springs at a very low cost from an LWB owner who had converted to springs. They were worn but in serviceable condition. At least I have a spare. I cleaned them up a bit and coated the "O" rings inside the top fitting with a small amount of petroleum jelly on the end of a blunt probe, and stuffed a bit of clean cotton into the fitting to keep grit out during the install. I also put anti-seize on the studs that accept the clips. After jacking the frame up just a few inches, the spring fit right in. The clips went right on with the push of a screwdriver, good thing I had spares as one flew across the shop, not to be found until I needed it no longer! The hose should push right back into the fitting, check to be sure it is in, the ring will pop back out a little, but will not fully extend until there is pressure in the line.

At this point I released the jack just a little bit to get the spring under some pressure and reconnected the battery. The suspension settled and adjusted after I turned it back on. The air spring filled up, and I checked for air leaks with soapy water in a spray bottle. I took the jack stand out from under the axle, and I was done. "Total time, around an hour."

Although air spring replacement on the 4.0/4.6 is very similar to the air sprung Classic models, there are some differences, including how to disable the air suspension, access to the parts, and in the type of clips used to hold the top and bottom pieces of the air springs in place. (Note: there are very good illustrated instructions for the operation on the Arnott site at http://arnottindustries.com/manuals/index.asp). Remember to disable the air suspension first, at least by opening the rear hatch and a door, or other methods described under "Disabling the Air Suspension" above. Regarding the fastenings, the 4.0/4.6 models use "R" shaped pin/clips on the rear, rather than the spring clips used on the Classic and on the front of the 4.0/4.6. Also note that the official shop manual requires removal of the plastic wheel well liners; this is not really necessary, and in the case of the rear springs, barely improves access at all.

Workshop Versus Field Replacement of P38 Air Springs
Please bear in mind that the official instructions and the ones on this page assume access to normal home workshop tools, including jack stands to support the chassis at an elevated height while the axles are being worked on with the jack or jacks. Having had to replace an air spring in the field without these luxuries on hand, or even any rocks in sight to rest the chassis on, I realized a quicker and dirtier method was called for! I found the job could be done with a single jack, no jack stands and without removing any wheels or wheel liners. Basically, you can just use the stock jack to raise the affected corner of the chassis, detach the fixings, and take the spring out. Details of this field replacement method are given at this link on the Air Suspension Field Repair Page.

P38 Rear Spring Replacement
Both Ron Beckett and I have replaced the rear air springs and found it to be quite easy. Ron reckons he could now change a set of rear bags in under 30 minutes - assuming a complete air spring, not just a bellows-only replacement, which is less expensive but takes more work -- see "Air Spring Bladder-Only Replacement" below). (When Kevin Kelly read Ron's 30 minute estimate here, he thought he was exaggerating, but now after replacing both rear springs on his Range Rover he entirely agrees).

Gaining Access to the Top Spring Clips
The workshop manual tells you to remove the rear inner wheel well liners; this is not necessary and unlike the front springs, makes hardly any difference to access (only a couple millimeters more room where the plastic liner hangs down). If for some reason your liner hangs down more than a few millimeters it is easier to make a small cut in the liner than to remove the entire thing. Nor do you even have to remove the wheels.

Tools: Ron suggests one pair long nose pliers to pull the retaining pin, one 6-8" long flat screwdriver to depress the air hose collect, floor jack(s) (you need a lot of lift to get the stands under the chassis). Two chassis stands. Kevin adds an optional mini LED light (photo at right) to see into the little gap between the wheel well liner and the frame where the "R" pin and air line are located. Ron, Kevin and myself all found the pins came out easily, but on adverse climates they may be corroded on, and you may need a 8-12" metal hook to "hook" the end of the top "R" pin and yank it out, and a hammer to pound out the bottom "R" pin.

Ron's Procedure Using Two Jacks
1. Pull the bottom "R" shaped pins to release the bottom of the air spring.

2. Lift the car fairly high on both sides and support it on stands under the frame just forward of the rear wheels. Ron used a jack on each side of the rear axle, then put chassis stands under the chassis. This is because you will need to hold the body up whilst lowering the axle to fit the air spring. Ron found it beneficial to use two jacks so you can lower the axle evenly (he used two trolley jacks).

3. With the suspension hanging, disconnect the air line at the top (see "Disconnecting the Air Line" in the Classic section above, and the photo below right), pull the top pin or "R clip" (see photo below right) and it's dead easy to pull the spring out. (Some owners have found the spring is corroded in place and is harder to pull out; of this is the case brute force may be required -- there are no other attachments to worry about other than the two pins you have removed). Ron and I were both able to access everything without removing the rear wheels. If you live in an area where corrosion is a problem, getting the pins out may be harder, and require removal of the wheel arch liner for better access.

4. Fit new spring and reinsert top retaining pin. Fit air line - just push it in. Jack up axle evenly on each side until the bottom spring plate enters the hole in the axle. If you don't raise the axle evenly a bag can easily pop off the piston. This happened to Ron but he found it was easy to refit -- he lubed the piston with a bit of kitchen washing up detergent and it popped straight on.

5. Fit bottom clips. Do other side, remove chassis stands and lower the vehicle. Start the engine (doors and tailgate closed to allow the EAS to work) and check that the car rises OK -- assuming it does, you are done!!

rear fitting

Genuine rear spring (top) and new aftermarket Arnott Industries replacement for 4.6. Both top cap and bottom piston on the new part are made from fibre filled plastic. The complete Arnott rear spring assembly is US$170 versus about US$280 for the genuine part. Unlike the genuine part, the new one also comes with a lifetime warranty. It is also about 2 inches longer than the original.

Photo taken by Ron Beckett from under right rear wheel well looking between the chassis (frame) rail and the wheel well.

Press the brass air fitting in to release the air line and pull the air line out. Do this before removing the R-clip, otherwise the spring may drop down and make it difficult to get to the air line collet. The R-clip can be withdrawn with a hooked bit of wire but to refit it, you will need pliers.

Kevin's Procedure with Only One Jack:
Kevin likes to do most auto repairs one side at a time, so if he forgets how something goes back together he can look at the other side. He took one wheel off to inspect his brakes and used a jack stand, but if doing it again he would leave the wheels on and omit the stand, since he does not need to get under the vehicle and even if the jack fails the vehicle will just fall to the bump stop. He recommends the following sequence:
1. Open the hatch and at least one more door to deactivate the air suspension (the hatch is good because when you jack up one side a door can close by itself).
2. Pull the bottom "R" shaped pins to release the bottom of the air spring.
3. Put the floor jack under the frame and lift until you can see the air line with your flashlight above the tire.
4. Hold the air line in one hand and press the metal collar with the screwdriver to let the air out (wear glasses so escaping air can't blow anything into your eyes).
5. Pull out the air line and put a piece over the top of it.
6. Pull the top "R shaped pin" and the spring will drop out (you may have to wiggle it a little bit).
7. Install the new air spring (the mini LED light lets you see what is going on). First put in the top "R" pin in then slide in the air line.
8. Lower the frame until the bottom of the spring goes in to the hole and slide in the bottom "R" spring and you are done.


Air spring ends showing "R" shaped clips and "D" shaped mounting protrusions that have to be lined up.	Right rear of Kevin's RR with the spring removed. Photos courtesy of Kevin Kelly

John's Procedure With Only One Jack:
Having only one floor jack, I raised the suspension to "high", opened the rear hatch to disable the EAS, then jacked up one side of the chassis a bit more so as to access and remove the top spring clips and air line. I then removed the lower clips and the old spring, and inserted the new one, juggling the jack height and the spring bottom to make its top seat evenly in its mount so I could insert the top clip. I then seated the bottom of the spring, inserting the bottom clip and the air line. I lowered the jack so the chassis was a bit below the high setting, then started the engine and shut the hatch to let the spring inflate itself and lift off the jack.

John's Field Repair Procedure With One Jack and No Axle Stands:
The above assumes access to the usual garage tools and axle or chassis stands. My simplified procedure for replacing a spring in the field without these conveniences, and using only the stock tire change jack, is described in this section on the Air Suspension Field Recovery page.

P38 Front Spring Replacement
The fixings and connections are slightly different for the front springs. Ron Beckett and Kevin Kelly both contributed photos for this section, whose text is largely from Kevin with modifications from my own experiences. Realistic total time for a single spring change is about an hour if you have not done it before.

Disabling the Suspension
Kevin left the tailgate and two doors open to avoid the possibility of reactivating it if a door got bumped closed.

Access to the Springs
The lower end of the spring is easily accessible from beneath the vehicle, but the top is harder to get to. On LHD vehicles, access to the left spring is poor due to the brake servo position, and as shown in the photos below is greatly eased by removing the air intake plumbing (a job of less than 5 minutes).


Access to top of front left spring is awkward on LHD models due to the clutter in the engine bay (left), but is greatly eased by removing the air intake filter, MAF sensor and plumbing so you can see the top of the spring (right).

Access to top of right front spring is easy on LHD models. (Photos by Kevin Kelly)	Removing the plastic fender liners makes access to the front springs easier. Photo by Kevin Kelly shows spring half out. (See photo further down page for details of fender liner removal).

Jacking up the Vehicle
First, jack up the chassis and support on stands. If you plan to remove the wheel arch liner to improve access to the top clips (see pros and cons under "Remove Air Spring Top Clips" below), break the wheel nuts loose, jack up the axle and take the wheel off. Kevin has heard warnings that the height sensors on the P38 can be damaged if the axle is allowed to hang free, but after removing the wheel I used the jack to lower the axle a bit to improve access. Kevin, on the other hand, supported the axle on stands and used the jack to manipulate chassis height.

Disconnecting the Air Line
The shop manual recommends system depressurization before any air lines are removed, but we have not had any problems skipping this step as long as the EAS is disabled by opening a door. If you start with the suspension at normal height, jack up the chassis to at least the "Hi" level, and lower the axle a bit, there is not too much pressure in the "spring" being removed. (This assumes your valve block is not leaking). Of course, if you are replacing a spring with an air leak, pressure in the spring will not be a problem since any air will soon leak out. Before disconnecting the air line, clean the area. The air line is released by pressing down on the brass flange around the air line (Land Rover calls this the "collet flange") and pulling up on the air hose. Kevin found that as on the Classic a 5/16" open end wrench is the perfect size to push the brass ring down. After pulling out the air line, Kevin put a piece of tape on the end to prevent dirt from getting in.


Fixings and air line at top of front spring on P38 (Photo courtesy of Ron Beckett)	Top view of new and old front springs showing clip locations (Photo courtesy of Kevin Kelly)

Remove Air Spring Top Clips
The plastic fender liners inhibit access to the two metal clips that connect the top of the air springs to the body. With the liners in place, Kevin found it very difficult to "lift and push" the clips at the same time by reaching down with a standard flat blade screwdriver. So, he ended up pulling the inner fender liner for easier access. If you do this, it is a good idea to buy a couple of the two-piece fender liner retainers as spares, since it is easy to damage them. Similarly with the spring top clips, a couple spare clips are handy in case you break or lose one. The used springs that Kevin bought on eBay all came with top clips so he had eight spares.

	Top of this picture shows the two parts of a clip -- the stud (top left) and the body (top right). The bottom of the picture shows a clip in the assembled position (bottom).
Removing the Fender Liner (illustration at left kindly supplied by Hiran, and at right by Ron Beckett). There are several cheesy plastic clips that hold it in place. Note close-up of a clip in lower right corner of left picture.	To remove clips, first the center stud needs to be pulled out. This is the hardest step to do without damaging the stud. Then the body of the clip can easily be pried out.

I have done the operation with and without removing the fender liners. The cheesy two-piece plastic fasteners that hold the liners on are hard to get off, but removing them definitely improves access to the top clips. However when a spring failed in the field I was not able to simultaneously support the chassis and axle to allow wheel and liner removal. Instead I was able to reach and release the top clips by hand. The outer one at first appears almost impossible to access, but I found that by bending the wheel liner in a bit I could get my hand behind it from below and easily reach the clip (see photos below).



Top picture: close-up of a top front spring clip (courtesy of George Wong). Lower left picture: position of right front top outer spring clip on author's Range Rover 4.0SE (fender liner removed).	Approx position of same spring clip (wheel liner in place). For access, bend plastic wheel liner outwards and reach behind it with hand. This can be done with wheel liner and even wheel in place.

Remove Bottom Pin and Spring
The bottom of the front spring is secured by a long metal pin that is bolted to the axle. After removing the bolt (13 mm socket) you can pull the metal pin out of the bottom of the spring. Then, with the top clips off and the bottom pin out you can manoever the old spring out if you raise the chassis or lower the axle sufficiently.

The spring should come out easily, but if yours doesn't, because of salt on the roads causing corrosion, for example, don't hesitate to apply brute force, as there are no other fixings than the top clips and the bottom pin you have already removed.


Fixings of lower end of front air spring on a P38 Range Rover (Photo courtesy of Ron Beckett)	Bottom view of front spring, showing hole for lower anchoring pin/clip. (Photo courtesy of Hiran)

Installing the New Spring
Like Michael, Kevin purchased a set of used air springs from an owner who converted to coils. He picked the best looking used front spring, cleaned it up and coated the "O" rings inside the top fitting with petroleum jelly using a Q-Tip. He just set the new spring in place, slid the bottom pin in and connected the bottom pin bolt to the axle. He then lowered the frame (I raised the axle instead) until the studs on the top of the air spring went in the holes and the top clips cold be put back on. Then he replaced the inner fender and pushed the air line in to the new spring. The shop manual says "! CAUTION: When refitting the air spring, do not allow the vehicle to rest on the deflated air spring. The chassis must be supported until the air spring is inflated". So, with the axle still on the stand and the frame still on the jack to prevent the vehicle from sitting on the bump stop, he closed the doors and the hatch and started the engine and watched the new spring fill with air. After checking for leaks he put the wheel back on and lowered the vehicle to the ground.

John's Field Repair Procedure With One Jack and No Axle Stands:
The above assumes access to the usual garage tools and axle or chassis stands. My simplified procedure for replacing a spring in the field without these conveniences, and using only the stock tire change jack, is described in this section on the Air Suspension Field Recovery page.

Air Spring Bladder-Only Replacement (Classic & P38)

Parts Options:
In 2002 there was a worldwide shortage of the genuine air springs which at that time were only made by Dunlop as the genuine parts supplier for Land Rover. About then, Arnott Industries in the US started making and selling a welcome aftermarket replacement. Shortly afterwards, Airbag Man in Australia began making the OEM Dunlop airbags/bladders available worldwide at much lower prices than the dealer network. This development was soon followed by another US supplier, Strutmasters, making the "bladders only" available at even lower prices (along with coil conversion kits). Replacing the "bladder only" allows you to keep the top and bottom sections of the air springs. Some users recommend that if you still have the old aluminum style of pistons, you should keep them -- they are more sturdy than the newer plastic ones which have been known to get cracked by the strain imposed by maximum articulation.

Photo at right: Old and new bladders (new one is from Arnott -- see below) and bottom spring piston off the front of Ron Beckett's 4.6. The inside diameters of the top and bottom of the bellows are the same.

Arnott Industries is the pioneer in Range Rover air suspension replacement components. They were the ones who came to the rescue when the genuine springs could not be had at any price, and they are constantly developing new products for the Rover EAS systems (The owner even drives a Range Rover!). Currently, they can supply the rubber bladder only for US$91 (front 1EO6) or $107 (rear 1EO6A). Note their rear bladder when new is narrower and about 2 inches longer than the genuine part -- see picture above. Andrew Parker found they seem to be made with a more decay-resistant material, but they change in shape after a period of use to become wider and shorter -- closer to the genuine Dunlop originals. They are perfect for the stock air suspension setup, but Andrew's lifted Range Rover, is set up for more than stock wheel travel, and he found they would "burp" out air on full extension. However, as mentioned earlier, this is not a problem on the stock suspension setup. Arnott also makes fully assembled spring replacements, as well as air springs and related components for other vehicles such as the Ford-Lincoln-Mercury luxury car range that has been using them for many years to provide rear load leveling. Although the Range Rover springs use different caps and pistons for front and rear, the same Arnott bladder or bellow part used to be specified for both -- so I got one to carry as an emergency expedition spare for the whole vehicle! However Arnott now has separate part numbers for front ($91) and rear ($107) which appear to be identical for either Classic or P38 models. Bruce Sanders reported finding the ride in his 4.6 more twitchy over bumps after replacing his air springs with the Arnott units, but they are known to take a little time to settle in to their final shape, and I have not heard this from anyone else.

Airbag Man supply the air bellows worldwide for front (their part # AB0001) and rear (their part # AB0002) of all Range Rover models, with their own specially made versions produced by Dunlop (same factory as original units) thus providing the assurance of performance at least as good as original units (like some RR owners -- see above -- they state the Arnott units appear to be quite short once aged). Airbag Man's export price is A$110 - about US$80, but prices for Australian customers are higher due to taxes. Airbag Man's rear bellows are designed to be longer than the factory units as the originals start to leak and fall off once aged; this also allows a small suspension lift as has been carried out by Hardy Neale of Australia recently. Andrew Parker also confirms the Airbag Man's versions to be about 1.5 inches longer than the genuine part, and seem to work well for users like him with lifted suspensions and more wheel travel than stock. Terry Mueller of Houston, Texas reports "The Airbagman springs are super quality and I learned the hard way that you have to roll the bags down over the lower mounts completely in order for them to seat upon inflation, without kinking the bags and pulling them from their seats".

Strutmasters is a US manufacturer that comes from the direction of making coil conversion kits, but also supplies some air suspension parts for those who are not yet ready to ditch their EAS. They now supply their own versions of the air spring bellows for all Range Rover models (as well as complete air springs for the Discovery II). For US customers they are the lowest cost supplier of the "bellows-only" solution, charging only $79 for front and $95 for rear bellows. What is even more amazing is that their bellows come with a lifetime warranty!! They have a lot of experience in the air to coil conversion world, supplying conversions for Ford, Lincoln, Mercury, Chrysler, Chevrolet, Buick, Oldsmobile, Pontiac, Cadillac, Lexus, Range Rover and Jaguar air suspension systems.

Procedure with Air Spring Removed from Vehicle
Andrew Parker reports that he has found the P38 RR air spring bladders are easy to remove and replace with the air spring removed from the vehicle. He offers the following instructions.

"The cap and piston are mated to the bladder by the same means as a tire bead but sort of inside out. The bladder has the bead seated on a cylindrical form with a lip which is either molded on the plastic ends and turned in to the older cast aluminum ones. The bladder can be removed by fixing the cap or piston in a vise. Then with the use of three tire irons (not screw drivers as they don't provide the correct angles and forces to do the job easily unless you are tossing the bladder for sure) the bladder is pried off. The only care needed is to be careful not to mar the lip on the piston, especially the cast aluminum ones as the edge is easily damaged by the tire iron if you are not careful. The plastic pistons and caps seem much more harder to damage and are far easier to pry off as the lip is molded and not as sharp as the older style aluminum version. I should note the aluminum pistons are sharp and tend to cut the molded rubber lip on the bladder during removal. To abate this I have successfully sprayed silicon spray into the bead area as I pry the bladder to help reduce the cutting.

Prior to disassembly the orientation between the cap and piston needs to be noted so that with the new bladder installed the ends are clocked correctly so they fit in the frame and axle's mounting features. I used a silicone spray on the bladder's bead and forced the bladder over the piston and cap by hand to re-seat the bladder. You can use a low pressure air supply and a downward force to get the cap to seat if the folded mass of air spring bladder is giving you fits. But the building up of pressure in the partially assembled unconstrained air spring is not for the non mechanically inclined and proper eye protection should be used to assure you don't screw up and hurt yourself. With the silicon spray being still wet it is fairly easy to twist the piston or cap to re-establish the alignment of the respective ends when the spring is devoid of any air pressure.

Another way I have done this, to get the upper cap mounted, is to get the piston and bladder together. Then I mount them on the axle and install the cap into the frame. I then lower the chassis height so as to get the bladder and cap situated with the bladders bead lining up with the caps lip. I then use regulated low pressure shop air and a piece of 1/4" or 6 mm tubing which I have stuffed into the cap's collet. I introduce some air pressure and the spring magically tries to extend and seats itself on the caps upper lip, albeit with a bit of a snap. You may have to play around with the distance between the frame and axle to get this to work correctly.

I did this during the 3.5 inch lift I managed to install (see "Lifting the Air Suspension") as a test to seeing what one might do as a field repair with the spring not being removed. With the inner front fender panel removed you could do the fronts without much problem. However the rears are another chapter as the upper cap is shrouded in the frame making the prying almost impossible with the air spring in the vehicle."

Procedure with Air Spring Still Fitted to the Vehicle
From reading various accounts of people's experiences with this operation, it emerges that one of the keys is to clean the detritus off the plastic or aluminum top and bottom pistons after removing the old bladder, and to lubricate the pistons and/or bladder prior to fitment of the new one. Some people use water or dish soap as a lubricant, others have used silicone spray to lube the rubber. Below is a representative selection of experiences from pioneers who have performed this repair. Also, compared to replacing a complete spring, you may need to jack the chassis higher to get more space under the mount down to the axle. The complete airsprings have the bellows folded over inside itself thus making them shorter than what one can do when fitting just the extended bellows. (See the pictures below).

Dean Caccavo reports an unexpectedly easy experience replacing his air bladder without removing the entire air spring. The front drivers side airbag on his Classic was leaking, so he obtained a replacement bladder from the dealer for $120. He reports: "I switched off the EAS (under seat), raised the front chassis, removed the wheel and lowered the axle. The bag by now had fully deflated. The other bags maintained their pressure. The bag popped off the bottom when the axle lowered and with a minor amount of wiggling the top was quickly removed. If it took me 10 minutes, 8 of which were raising and lowering the car. I sprayed some lube on the new bag and popped it into place. Top first then bottom. Thanks to the [rro] list I was prepared for the "it looks to long" feeling and hung in. To create the proper folds, I removed the air line and used my air compressor to inflate the bag slightly and then mounted the wheel and lowered the car mid way. I replaced the air line with the EAS line and turned on the system. Magic - and I was done before lunch. 1 hour max. If I had to do it again (pass side) I could probably get it done in half that time". (Dean had been told by the dealer that they charged two hours labor for the job).

Chris McAuliffe also managed to get a new rear bladder on his 1993 Classic LWB without removing the pistons from the car. He reports: "I jacked up the chassis as high as I could on that side only and inserted jack stands. Removed rear wheel and cleaned piston. Then I stuck my fingers up inside air bag and pulled it all the way down. After wiping the bottom of the bag where it slips over the piston with a wet cloth I was just able to slide the bag onto the piston while squeezing the center of the bag to make sure it didn't try to revert to being rolled up (seemingly it's natural position). Then I mixed a solution of dish soap and water into a spray bottle and squirted all the way around the piston / bag interface area. At this point I lowered the chassis about an inch, tire still off. This allowed me to slip the bag a bit further onto the piston. Then I replaced the tire and started the engine up. It pumped the bag up a little bit but it was leaking. I slowly lowered the chassis and at some point it popped on and the hissing stopped. I lowered the jack to about the point where it was off the bump stops and let the car take over from there. It took a couple of minutes but everything came back up to normal. A quick drive around the block confirmed that everything was in working order.

Ron Beckett unintentionally had to refit a bladder to a spring top in situ when he was replacing his complete springs on his 4.6 HSE. He reports: "When I couldn't pump mine up and finally got underneath to see why, I found the bladder had become disconnected from the top fitting. I refitted it situ as follows. I jacked up both sides the car and put chassis stands under the chassis, forward of the rear wheels. I found it is necessary to do both sides to get sufficient droop on the axle. (I found this out when I did the first air spring. I couldn't get it back in until I lifted both sides of the car. It came out OK as it was in fully compressed state whereas the new spring is not and is effectively much longer.) I pulled the bottom pin on the disconnected spring and removed it, leaving the top plate in position. I then lubricated the top lip of the spring and the top mount with a smear of dish washing liquid. The spring now just pushed on with hand pressure. No tools required. I then jacked up the axle, aligned the bottom mount and refitted the clip. Done."

Ron Beckett reports that a friend's 4.0/4.6 had a bellows change done by a local independent shop. However the mechanics said they won't do a bellows change again, as they found it to be a lot more work than a complete spring change. The shock absorbers had to be disconnected to allow the suspension to droop even more because of the overall length of the spring being longer owing to the fact that the bellows wasn't folded back inside itself.

User Experiences with Different Brands

I have received a number of different comments about the different available brands of air springs. Some of the user comments are included below to help readers make up their own minds!

Some users have found that the basic Arnott (Generation I) replacement springs are initially longer than the original Dunlop springs, but gradually shrink so they become shorter than stock, which could cause leaks at full articulation. The ones supplied by Airbag Man) are designed to solve this problem and the rears, for instance, are longer than stock. Arnott has now (September 2005) produced a new "Generation 3" design that gives 2 inches longer travel than stock, and use a piston design similar to the Mk III Range Rover, giving a softer off-road (Hi) ride and a firmer highway ride. I have personally tested these springs on and off road, and found them to be a definite improvement over stock -- especially in the high and low settings. A full description of the design and my experiences with it appears on the Arnott Generation III spring upgrade page.
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Theodore Williams reports: "I recently purchased 4 complete airbag assemblies (presumably first generation) from Arnott Industries and installed them on my 98 4.0 and found the ride to have the same quality as the original springs. John Rogers reports changing his worn out springs to Arnott units (bellows only). He found the hardest part of the change was getting the residue from the old springs off the pistons. Afterwards, he felt the ride was softer than with the stock springs.


Top mount removed from bladder of rear spring	Spring bladder cut in half to show design (photos courtesy of Kevin Kelly)