[ratbrain]

Looking for help from the forum.

I have a MY2006 RRS S/C. Recently had a coolant pump failure. Took it in and had the pump replace , car back the next day.

The last week since i've had it back, the car accelerates thru the gears fine until about hitting 35-45 mph. Approx when you think its going to **** from 3rd to 4th, the car never does. I was on the free way doing about 65mph and the rpms were at 5K .

no matter what i do. press hard on the gas/ gently/ hold back a little, the problem is still there.

i've owned a few MBs before this and i know that the transmission adjusts to the way the car is being driven and i thought the dealer had reset something to this affect.

but no, i brought it in today. took a drive with the tech and showed him the problem.

The frustrating part is that i do have the spare on right now as one of my 22s has a slow leak and is in a repair shop. the SA calls me back and tells me that i have to either put the missing 22 on or they will charge me to take off the 3 22s and spare to put a set of stockers on to rule out tires being the problem.

i say, thats ridiculous! they quoted me $230 to take off the tires and put stockers on to test! i say, lets play devils advocate, you are telling me that putting the spare on any RR or RRS causes this transmission problem!?!?! its a transmission issue. lets just fix it!

i say BS! sorry for the ranting nature of my post, but i want to get all of your thoughts and inputs....

additional info: car is at symes in pasadena CA

 

[umbertob]

What size 22s are on the car? For once, I think the dealer may be 100% right in suspecting the aftermarket wheels. If the stock spare you have currently mounted as a running wheel is fractionally smaller (or larger) than your remaining 22s in overall circumference, the transmission may think you are cornering (as the speed sensor of the "smaller" spare wheel would send mismatched speed info to the tranny module), and prevent upshifts. I think the corner recognition system kicks in if it detects a variance of as little as 1 kph between wheels speed on the same axle.

 

[ratbrain]

my 22s are 22x10 tire size 285/35 .

i agree with what you are saying partially. however, i've had the spare on more than a few times and this is the first i've ever experienced this problem....

i also thought by that rationale, even if someone were to have the stocks on, putting the spare in place of one of them should cause this problem.

that doesnt seem likely to me....

 

[umbertob]

On paper, there is about a 1.6 mph difference in "rolling" speed between your 22s and the spare you are using right now (assuming the spare is a full size one, 255/50/19... They used to be that way on 2006s before Land Rover got cheap and started installing compact donuts on later model years), and although it may not be as large in the real world due to wider 22" rims, the difference may still be large enough to trigger the corner recognition thingie that won't allow upshifts in your car... What matters is the overall circumference of the wheels. If your 22s were sized 265/35 for example, they would be virtually identical to the stock setup (and the spare), so you would most likely not experience any issues.

Is your spare wheel mounted on the front axle? Perhaps moving it to the rear - so at least the wheels in front match - might help. Either way, the sooner you get the missing 22 fixed and reinstalled, the better. :wink:

PS: I have found the ZF tranny troubleshooting manual, scroll down to page 12: download/file.php?id=1415

 

[ratbrain]

i hear what you are saying. ill wait to see what the SA has to say today when he calls.

unfortunately my 22 is being repaired for small leaks along the seal between the rim and tire. there is some chrome peeling on the inside lip and the shop has to disassemble, strip, repair the face, and then outsource for chroming.

its not going to be quick.

so by what you are saying, even if the stocks were on, this problem could exist? i still am having a tough time fully believing that. as i've had the spare on with my 22s about 4 different times and have never experienced this type of problem.....

 

[umbertob]

so by what you are saying, even if the stocks were on, this problem could exist?

No, because revs per mile of stock wheel/tire combos (whether you have 19 or 20s) always match the spare's that is under your car. Your 22s don't. I don't know why you didn't experience this issue before. Perhaps the spare was inflated more than it is now, or mounted on the rear axle...

 

[ratbrain]

ok. i get what you are saying. that does make a little more sense.

but its true, i know that i've had the spare on the front at least 2 other times and the last time was just this past dec/jan.

i always check the tire pressure of the spare before i put it on if i can and the pressure was good , so i did not adjust the air pressure..

weird... ill wait to see what the SA says. i will make the suggestion to them of swapping the spare to the passenger rear and the 22 back to the passenger front so the front axle has both 22s on them.

hope they can determine what the problem is....

 

[ratbrain]

thanks umbertob for your thoughts/insights.

the sa insisted i put the stocks back on. so hrs later, i've got the stocks back on with the spare still on the front passenger.

i must eat my words and admit the SA was correct. the problem is gone.

i guess i will leave the stocks on w/ the spare until i get my refinished 22 back so i can put the whole set back on.

thanks again.

 

[umbertob]

If your 22" wheels are going to stay on for the long haul, you may want to either consider buying a fifth 22" wheel/tire and keep it as a spare (it will fit under the well, although it will "hang" a little lower than the stocker), or switch the size of the existing full size spare tire, from 255/50/19 to the cheapest 255/55/19 tire you can find, fitted on the same 19" rim. The overall circumference of the 55 profile tire would closely match your 22s and you would not risk having this potential issue in the future, should you get another flat while far away from a tire shop...

 

[ratbrain]

thanks man. sound advice. unfortunately, i picked up my current 22s used, although they were in like new/great condition.

i've been thinking of getting a new set, but i think i will buy a set of 5 this time. i can always put on the spare if im literally stuck on the side of the road. when i get home, i can put on the full size back up.

one extra round of dismount and remount, but at this point, im definitely familiar with the jack and spare....

the odd thing i still cant figure out is why now? i know i've had the spare on the passenger front at least 2 other times, but i've never had this problem prior to this week.

 

[IMMensaMind]

I just had this exact same problem pop up as well - all due to a brand new dealership service nightmare about which I will go into detail when I have more time. Short version: dealership alignment incompetence has destroyed every tire on my RRS, and nearly got my daughter and I in an accident - or worse.

 

[gooseyloosey]

dealership alignment incompetence

Been there. I don't think they understand how to do alignments at most dealerships--not only LR.

I take all my vehicles to an independent tire shop who seems to understand the difference beteween the + and the - sign in front of the spec'd number, and my anal retentive desire to have the steering wheel in the 9-3 position and not in the 10-4 position.