Two new M6's plus steering wobble concerns

[Palmnuts]

Hi all - I've initially posted this on the M6 forum however, as the M5/6 are technically the same cars under the body, and this is a technical related subject, I thought I'd also pop this in the busier M5 section to see if any M5 owners can give some insight.

I'm one of the UK's very rare F13 M6 owners which I've owned for a few weeks and am extremely impressed with it - indeed, having come out of an SLS AMG, I reckon the M6 is the better all round car, which surprised me somewhat.

In fact, I'm largely so impressed that I've just ordered a new Competition Pack version Yep, even though I've only had my current M6 for little over a month (which I bought as a 8-month old dealer demonstrator), BMW UK are giving some serious contributions against new M6's so I managed to get close to 20% off list plus 4 years 0% APR on a personal contract, all of which makes the new car barely more expensive than my current one And this is despite my new one being spec'd with £18k's worth of Competition Pack, Carbon Ceramics and B&O, none of which my current car has.

Anyway, one thing I don't like about my M6 is the seemingly incurable steering wheel wobble that happens from about 95mph upwards. It's typical of unbalanced wheels, yet I've had the car Hunter Roadforce balanced three times with little success. The dealers in the UK aren't overly helpful as they say the speeds are beyond what they should be testing the car at (which is true, if a little difficult to swallow given the type of car it is!). The wobble is slight, but still very noticeable and just shouldn't be present.

I'm less concerned about my current car as it goes in three weeks. Also, whilst there are maybe 2-3 threads regarding this on the M5 forum and Pistonheads (although none have any resolutions mentioned), the volume of complaints online just isn't enough to indicate it's a typical characteristic of the car (unlike if you search for the same problem on the F30 3-series, of which there are 40+ page threads on this subject!). Ultimately, I just can't believe other M5/6 owners would put up with such a thing without mentioning it!

In any case, even if it was characteristic of early-build cars (as my current one is), with my new Competition Pack version having revised suspension, bushes, steering rack and wheels, I'll be astonished if it demonstrates the same problem. I've even spec'd the competition pack wheels on the new car despite preferring the design of the current 343M's....just to make sure I eradicate as many possibilities of the cause of the vibration (actually, whilst they look average in pictures, I reckon the Competition Pack wheels will look just fine in real life and it'd probably be wrong specifying this option without the right wheels!).

As I'm confident the wheels are correctly balanced, I honestly think it's something else to do with the car so was wondering if anyone else experiences similar on their M5/6 and if so, have you found a resolution?

Heres a few pics of my current totally standard car, in San Marino Blue with Silverstone interior....

[Jay-K]

I believe your car is an F12 sir if I'm not mistaken, btw why would you give up on the sls?

[Rob///M5]

Not characteristic for the car. I had the same thing at 80 after a new set of PSS tires. Had it rebalanced and made it a little better. Drive the car very hard in the mountains (left some rubber on the roads), and voila, vibration gone.

Not a very scientific recommendation, but worked for me.

Sounds like a hell of a deal on the M6.

[Vic55]

M6 coupe is an F13.

[stealth.pilot]

I had steering wheel vibration above 95mph too when my M5 was delivered. Took it in for wheel balancing, but the dealer diagnosed it as a tire defect in the front left tire. They replaced the tire and the car was perfectly smooth thereafter.