X5 Gearbox/Transfer Box Issues Fixed by BMW Star Rated Tyres

[acarty]

Hi All,

New to this site; I just wanted to share my experience with my 2004 X5 3.0d.

Since I have owned it (3 months or so ago) there has been a whining noise (almost a bearing noise) coming from the car when travelling at slow speeds. I was preparing for a transfer box replacement as I don’t think that the gearbox would make this kind of noise. In addition when playing about with my laptop plugged into the car, I thought it would be a good idea to reset gearbox adaptations, as if it were a new gearbox. Since then it was jumping down gears harshly (the dreaded lurch) in addition to a bang  of it engaging in gear when revs were applied at slow speeds. Again, I was expecting the worse of a new gearbox. My advice to anyone thinking about it: DON’T reset the gearbox adaptations!

After a fantastic conversation with the dealer, he recommended I look at changing the tyres to BMW star rated ones (and I thought here we go, they just want me to spend £XXX on a set of Bridgestone tyres). He did explain this was to prevent the transfer box from `winding up` at high speeds as different tyres may have different rolling road radii, causing transfer box problems such as a whine (sounds familiar). After that he said it would be an oil change, followed by a gearbox software update and if this didn’t resolve the issue a replacement gearbox.

Due to the rear tyres wearing on the inside (as I have learnt the X5s have a quite large negative camber) I decided I would put a set of Bridgestone ER30 star rated tyres all around, what harm can it do?

I can honestly say this is the best decision I have made on this car yet; no whine whatsoever and no gearbox jumping! I wanted to ask however when I slow down to a rolling stop, after a few seconds of slow rolling I feel the car slowly drop from 2nd to 1st gear; however this is not a gearbox slam and doesn’t really lurch. Should the X5 drop into 1st gear when rolling at speeds <5mph, or should it stay in 2nd until the car has completely stopped. What does your cars do? This is nothing really, I just want the car to be right!

I have been doing other jobs on the X such as fixing the self-levelling suspension issues and others, so will post these up to help others with the same issue.

Fantastic car, loads of pulling power and comfortable to drive, I love it!

Cheers,
Andy.

[X5Sport]

Hello & Welcome

Very interesting first post.

Now here's a rhetorical question for everyone who cares to think about such things.......does fitting non-OEM star marked tyres result in premature transmission failure? 

I know for my X5 it was a torque converter failure and only star marked Michelin Diamaris had been used, and the TC failure was very early in the 'life' of the car.

But could it be that the slight variations in rolling radii that fitting either one pair of tyres only, or non star marked,  tyres might result in broken transmission parts?  I would have expected the tolerances to be a little wider to allow fir this, but.......

Musing completed...

Richard

[acarty]

Surely the answer to that should be no, but with BMW who knows? Certainly in your case it shows it wasnt the tyres at fault, however just by changing the tyres the grinding feeling/noise that i was having has gone. Like you say the tolerances should be much bigger, maybe they are like they are for performance reasons?

Does your X5 drop down to 1st gear smoothly like mine when rolling at very low speeds or should it stay in 2nd?

[X5Sport]

Mine only used 1st in Sport mode I think.  I sold it a couple of years ago now so things like that are beginning to fade from memory.... :-[. It may have been in 1st when 'creeping' in traffic and then went straight to 2nd if power was applied.

Like you I think the tolerances ought to be better, but.......

Richard

[rhinoman]

Related question maybe? Do the tyres on an X5 wear out at the same rate front to back? Inherited different pairs on ours when we bought it that were worn at different rates so don't know yet.

[Steamyrotter]

All tyres will wear at different rates..

There are too many variables in there to quantify and predict...
Tracking, camber, construction, driving style, surface, front to rear power transfer etc...

as an aside..
I don't really subscribe to wind up on these as that is usually only a factor on locked diffs.....
These should unwind themselves prior to any issues arising,
However cannot argue with results from OP but could be coincidental??
There could be other factors in there maybe?

[Johnny-p]

I'd be interested in the answer to this aswell..

Bought mine with odd tyres so replaced all four 3k ago along with a full laser alignment..

John

[X5Sport]

I had three sets in my E53 with the first two being * marked Diamaris.  All wore at a similar rate and were replaced as sets at roughly 26,000 miles a set.  I replace my tyres @3mm tread remaining.  The E53 was sold with the 3rd set (Dueller RFT) and they were wearing evenly too.

My current E71 has 1mm wear difference across the four tyres which (to me) says they are also wearing evenly front and rear.  It is shod with Dunlop Sportmaxx RFT from the factory.

Richard

[graemeX5]

[quote="Steamyrotter"]
All tyres will wear at different rates..

There are too many variables in there to quantify and predict...
Tracking, camber, construction, driving style, surface, front to rear power transfer etc...

as an aside..
I don't really subscribe to wind up on these as that is usually only a factor on locked diffs.....
These should unwind themselves prior to any issues arising,
However cannot argue with results from OP but could be coincidental??
There could be other factors in there maybe?
[/quote]

From my days with vauxhall cars the 4x4 turbo calibra and cavalier had probs with the transfer boxes.

It seemed to be if the front pair and rear pair of tyres were more than 2mm different in depth then it would cause system to go into limp mode.

A lot replaced the tyres as a set of 4 which solved it others converted the cars to 2 wheel drive to avoid it occurring again.

So I think there must be something in this as I know the car monitors the tyre pressures / radius as I have had the light on. Therefore it would be logical it would link into the 4x4 system which is dependant on the wheels rotating the same or within + or - small tolerance.

[ChrisLux]

I've got '05 3.0d and when I'm slowing down to traffic lights it goes down the box until I'm almost at a standstill
and then you feel it go down into first (maybe it's 5 mph not sure) but I'd say what you're experiencing is OK

[Smeeagain]

Sorry this probably appears as. Daft question but what are star marked as opposed to non star marked tyres ?
Smee

[X5Sport]

Star marked means (allegedly) the rolling diameter has been 'shaved' to ensure a closer match front to rear.  It just means it's the official 'BMW Version' of the tyre.

Why it's been shaved is open to debate, but it makes me wonder if the rolling diameter differences could indeed be significant in some way that BMW are keeping schtum about.....

R

[fenj66]

when you say "shaved" does that mean that the star marked tyres actually come new with less tread on them than a "standard" tyre?
if thats the case then fitting a pair of part worn standard tyres would have the same effect wouldnt it?  :blink:

[X5Sport]

That's what the post I read a while back said.  I can't remember where on tinternet I came across it.  I don't think it was a lot of tread off though.

It only applied to staggered set ups on BMW cars as the tolerance in terms of different rolling diameter is supposedly very tight and can cause 'wind-up'.

I would have expected the system to cope, but the difference of a standard over a '*' marked can be as much as 23-25mm on the rolling radius front to back.

There are different versions for all sorts of cars such as
MO for Merc
AO for Audi
VO for VW
N1, N2, N3....etc for Porkers

Richard

[kkx5]

You could be right. When i got the car in 2011, had * rated bridgestones front+back, front 6.5mm, back 4mm and noises on TC. Got new summer tyres in march 2012 , front+back, same brand. Tread 7.5mm. No noises. In same year I put new winters on, front+back, tread 9mm. Transfer noises strait on! 2013 spring, summers on...no noises. 2013 winter...Winters on, half of the 2012 noise. Drove Poland and back for christmas. No noises. Obviously they worn down. Checked tread: 7.8mm. If think, thats OUR answer. Tyres can not be different front-back, they can't be different brands and can not be too "new"