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1995-2002 Range Rover P38A
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Discussion Starter #1
Hiya,

First I want to thank the guys who run this site and forum and the contributors who have helped me out on so many occasions with super information that saved me tons of trouble with my much loved P38, turning it from a nightmare into a pussycat, and helped me with various woes including every possible EAS situation.

I recently started getting some random wandering on the car, but it works very hard indeed, so I quickly found a few things to do, it needed new front tyres, I didn't like the feel of the front shaft, and a suspect ball joint was found.

Day 1 I ordered the new front tyres online, they arrived in 48 hours, I banged them on. The other parts would take longer and I had house guests so i continued to use the car.

Went for a few trips with guests and noticed the front vibration was getting bad, so I kept it slow and below the vibration speed and secretly wished for the new front shaft to arrive.

A week or more passed and a ski trip was on the cards, I reckoned the car would be ok, doubled checked the joint and took the slow scenic route. Later that evening we took a faster road home, downhill, and I let the car run closer to the vibration speeed and occasionally into it when holding up traffic blasting home after a long day on the slopes.

Next morning the new shaft and steering bit were there, I quickly fitted them and started the car, went to full lock to turn and WHOA! the car literally jumped wheels, front and rear. Badly. The bearings were creaking under such load and the wheels, tyres and shafts were jumping to adjust to about 6 inches of rotation to catch up!! Park the car and spend a weekend reading here.

With all the information at hand, the VC was diagnosed and ordered. As I live on a mountain, no recovery was possible, so every repair for me is a field repair, so all those details are below.

Following fitting, smiling, I took the car out, hit the motorway, got to 80kms ok, 90 ok but after 30 seconds MASSIVE vibration from the front. This is with new everything including a new F diff last year.

I slowed and slowed, but the vibration came down with me until I was in the hard shoulder doing 30kms. After a while I realised that the feeling had changed in the car and loosened again, and realised that for some reason the NEW VC was heating up and grabbing, locking front to rear.

didn't make any sense, so what if front and rear were locked on a motorway? It took 48 hours of head scratching to figure out what had happened. I suspiciously went to the new front tyres ordered online and found they were 235/65/16 not 235/70/16!! The difference at speed was heating the VC and locking up the car. It wouldn't lock under 70kms, anything over and you could feel the car immediately tightening and wandering. Even after 20 mins of slow running, it would tighten.

Got four new (same size ;-) ) tyres and voila, the car drove like brand new. Beautiful.

A salutory lesson, a stupid mistake that I didn't catch at the tyre yard (I ordered correctly) and remember I had had this wandery feeling in the car before, and that came down to changing only the fronts from 4 poor tyres, leaving an 8mm differenc! At speed, you WILL fry the VC, until it can't recover one day and stays locked.

In addition, the massive vibration is the front diff on the overrun while the rear is driving forward, completely the wrong pressures it was designed for, and that will also join you in the cabin soon at that rate.

Thank you all again for the great info, and there isn't a detailed guide out there, so I hope this helps someone.

You will need:

Full socket and spanners set with long and short extensions and a knuckle joint.

30mm socket and extendable bar.

A 9/16ths socket and spanner (the sizes on mine are decidedly mixed imperial and metric)

Good quality pullers

Various axle stands and jacks, to free shafts for bold access.

Torque wrench

Good quality gasket cement.

The downloadable PDF workshop manual for torque settings (cant remember where I found it.)

Something to stop the stones hurting your head.

Jack up the car.

Drain transfer box.

Remove front shaft.

When removing the shaft from the difficult rear flange, two of the nuts can be difficult to get a socket on, you can use a long ring spanner on the nut, with the spanner up into the tunnel against the body, then rotate one of the rear wheels to undo the nut. But triple check for tightness if you use this method to re-fasten (like I said: Field repair). Pull the shaft and treat yourself to a new one from island 4x4.

While you're there, undo pretty much all the nuts & bolts on the gearbox mounting, don't try to take away the crossmember, you don't have to. Undo the nuts on the rubber mounting top and bottom. Don't do as I did and support the gearbox with a trolley jack and a lump hammer, find your own dangerous way.of doing this. It won't move at all when you undo the bolts, it just allows you to move it up for the mounting removal.

Lock the handbrake, then with an extension bar and a very good quality 30mm socket ( i used facom as I'm in France, would have preferred a Snap on). With both feet on the bar and your arms pulling like hell on the chassis, undo the flange nut. It's a big push so be careful not to unseat the socket and damage that nut.

Discard and replace if possible as it's a Nyloc, if you're on a mountain in the south of France far from Wurth, just try to keep the gravel out of the threads till you need it again.

Using a good quality bearing puller, again Facom in my case, pull the flange off the VC. Mine walked off.

Undo the bolts on the VC case, you'll need a long extension and a UJ knuckle joint.

Mark their positions, case and transfer box.

Usin a rubber hammer or a wooden drift, tap the case at the bottom flange rotationally, and it will give easily enough.

Now remove the rubber mounting that's in the way, it's basically a block with a bolt fitted each side. Using a combination of inappropriate tools from a farm, jack up the transfer box off the loosened mountings, and compress that B*****d thing until it pops out as if there was never any knuckle blood involved.

Keep the transfer box jacked now and gently remove the VC and it's case by rotating/ pulling, pushing, crying etc.

Once out and away from the hated cramped world you've been in, tap the VC out of it's case, use a rubber mallet or softwood, be very very careful not to damage the oil seal.

Clean both surface with acetone or something similar, I can't stress this enough, you don't what to have to do this again because of a AFT leak.

Tap the new VC back in being careful not to tap it in off-centre. When it's properly seated about 2mm from flush, you're there.

Try to figure out what way you got the CV cover off and get it back in, re-assemble in opposite order.

Re-fill with 2.4 litres of ATF. I found a 2m bit of hose, stuck it onto a funnel and got the wife involved, they didn't put that in the manual, otherwise there appears to be no sane way to refill the Transfer box.

Car is now like new.

Best regards,

Mike

Errors and ommissions and plasters welcome.[attachment=4:2kjeso6r]DSC07358 (Small).JPG[/attachment:2kjeso6r][attachment=3:2kjeso6r]DSC07360 (Small).JPG[/attachment:2kjeso6r][attachment=2:2kjeso6r]DSC07365 (Small).JPG[/attachment:2kjeso6r][attachment=0:2kjeso6r]DSC07371 (Small).JPG[/attachment:2kjeso6r]
 

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Registered
1995-2002 Range Rover P38A
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161 Posts
Discussion Starter #2
Re: Viscous coupling field repair walkthrough and lesson learned

More of the pictures[attachment=3:2bcfs5gd]DSC07372 (Small).JPG[/attachment:2bcfs5gd][attachment=2:2bcfs5gd]DSC07377 (S[attachment=0]DSC07369 (Small).JPG[/attachment:2bcfs5gd]mall).JPG[/attachment][attachment=1:2bcfs5gd]DSC07359 (Small).JPG[/attachment:2bcfs5gd]
 

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120 Posts
Re: Viscous coupling field repair walkthrough and lesson learned

Great description and pics!! Thanks v.much for the info!! :thumb:
 

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541 Posts
Re: Viscous coupling field repair walkthrough and lesson learned

Kick azz post man! Thanks for sharing.

And killer view it looks like too.....
 

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Re: Viscous coupling field repair walkthrough and lesson learned

outstanding post! thanks for taking the time!
 

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442 Posts
Re: Viscous coupling field repair walkthrough and lesson learned

G'day Mike,great post very detailed pics.
Only problem i have is that you didn't replace the output seal as per your pics you can see that moisture has cause minor rust on output flange and on old spline of old VC. Also did you take any pics of the output bearing and why did you not replace it as well :think:
Great stuff any way as i maybe doing the same thing very soon as you have answered a few questions as i have a similar problem with viabrations intermitted ,cold hot etc
Regards Graeme
 

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1995-2002 Range Rover P38A
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161 Posts
Discussion Starter #7
Re: Viscous coupling field repair walkthrough and lesson learned

Hi Graeme,

Well technically one should, but the rust was v superficial and just at the seal and not inside, I performed the fondle test on the bearing and it felt good. Then I spun up the VC in the case, had a cup of tea and a few puffs on a cigar and it was still spinning happily after all that.

I don't have a press, so was grateful not to have to go elsewhere to do the bearing, but finally my ol jessie has 320K on the clock so life-ing parts is not an option.

If this was being done in a shop I'd expect a new seal and bearing for sure. Having done this once, if necessary, I'm confident I could do it again in under 2 hours.

The car is so silky to drive now, I've put more fast miles on it since I first posted, it's transformed in every way. Will probably put in a new rear shaft and re-balance rears now just to put the icing on it.

Regards,
Mike
 

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1970-1995 Range Rover Classic
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45 Posts
I did mine in my driveway. I found a used VC on a wrecked classic in a junk yard and took a chance. Cost me $20 US housing and all. I just unbolted the front drive shaft and then removed the bad VC, flange and all and swapped in the used one, flange and all and reconnected the front driveshaft. The used VC was good and I was back on the road. I didn't put any type of sealant between the housing and the transfer case. I may go back under and do it just as a preventive measure against water but I have no leaks and the output shaft seal on the transfer case was good. No fluid in the VC housing. I got lucky. I think the bearing and seal were replaced by the previous owner as he said he had put a VC in before.
 
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