BMW star rated tyres

[The Stiglet]

I purchased an AUC X5 E70 at the end of summer last year. I've only done about 3,000 miles or so but it's had a list of problems that BMW have had to deal with under warranty.

Specifically to this thread, it's needed a new front differential, rear differential, front hub, drive shaft and a transfer case. The car came with non RFTs, without a BMW star rating - Continental Sport Contact 3s on the front and Continental Sport Contact 5s on the rear. All have equal tread and wear on 20" wheels. The car was specced new with standard 19" wheels that were later upgraded to the 20" ones.

BMW have chucked money at the car to fix it but haven't provided me with any real technical feedback as to why the car needed two diffs and a transfer case, which seems crazy at 60,000 miles. It hasn't towed and was driven by the same lady owner for the last 5 years. My specific question to the Forum is, are my 'non-star approved' tyres the culprit? If so, should I replace them with starred RFTs?

I've seen the previous thread on BMW star rated tyres and included this quote below, which I would agree with but I'm now unsure. Any help would be greatly received.

dandle said:

The branding of the tyres is to do with the deals the tyre companies do with the manufacturers to get their tyres onto new cars. That is where they will gain most of their profit from people who buy the cars new and will generally stick to the original tyre for the first three sets (thats what they work it out to as a benchmark)the tyres are no different and not tuned to Mercedes or BMW spec infact the same size tyre is the same unit price to the wholesaler, weather it be AO, *, or MO. The thing anout the rolling radius is rubbish too, that is worked out on the profile change between the different width front and rear tyre.

People who have problems with BMW and tyres are generally either using poor quality or midrange tyres or they are mxing brands of tyre on or between the axles which these car are quite fussy about.

Edited by dandle on Monday 12th March 09:35

Link to thread

Edited by The Stiglet on Monday 23 January 13:47

[The Stiglet]

In the AUC check BMW are allowed to sell the car without star approved tyres. Therefore, I would strongly argue that any drivetrain issues be covered under the warranty as it's an AUC car with all the associated protection. Otherwise what's the point of buying AUC?

So far, they've spent a small fortune repairing mine but then I did have to reject an F10 535d earlier in the year and I wrote to the CEO complaining about my torrid experience with both cars.

The transfer case is getting put in this week but if my tyres are causing the problems then I'd like those replaced too. From my research, non starred isn't a problem on RWD or FWD or indeed, matched wheel sizes. The problem is staggered set ups and XDrive with chocolate transfer boxes.

I'm nervous because what else could possibly cause these failures?

[The Stiglet]

It's taken six weeks of negotiation between the dealer and the warranty company but they finally agreed to pay out on transfer box and I have the car back. The dealer was asked to measure the circumference of all the tyres, check the tread depth, tread patterns, weight of the tyres - plus a whole load of other tests. It seems like they tried everything to wiggle out of it. As they were fitting the transfer box they noticed that the prop shaft was fairly mauled so they've replaced that too. Overall, I'm very close to having a new car!

BMW also agreed to replace all my tyres with star rated tyres should I wish. I think I will be taking them up on that offer...

[The Stiglet]

Output Flange said:

Did they agree to replace them with new star rated tyres though? If not, I'd be inclined to fund the difference to get brand new rubber on there.

Yes, brand new. I was prepared to pay for it myself but negotiated this added compensation from BMW.

VerySideways said:

Star rated is about weight as much as it is about circumference - make sure you get a full set of matching star marked as part of the deal or you'll be knocking on their door again sooner than they'd like!

That's a frightening scenario! The technicians thought that the tyres wouldn't make a difference. The warranty company haven't been able to prove that there is anything wrong with the tyres either. It appears to be an internet myth which might actually be based on fact, which is very difficult to prove