Wheel wobble

[Mark Norton]

Yes it did seem high to me too, my problem had been with the wheels moving on the hub, resulting on inspection in indentations on the centre hole in the alloy wheel. I'd drive off on the motorway all reasonably O.K hit a bump then have even worse steering wheel shake because I believe the road wheel had slipped. I had tried the mushroom type wheel nuts which I still use, then went up to this high torque after finding this bulletin on the RX8 owners club forum.

Here is the info I found from the Mazda RX8 forum.

Mazda issued this bulletin on 23/2/2004 for the Mazda RX8 fitted with 18" alloy wheels.

Subject: " Snapping noise when turning at low speed."

Quote:

When the vehicle is making a turn with the front wheels receiving side force, the joint of the aluminium wheel slightly deforms, allowing the wheel and brake disc to slip against each other. This slippage causes the anti corrosion treatment to peel off the brake disc. The friction co-efficient between the wheel and the brake disc joint surface changes. As a result, a stick slip noise occurs.

Repair procedure:
Remove anti-corrosion treatment from mounting surface of brake disc and wheel with 100 grit sand paper, and clean mounting surface of brake disc and wheel with brake cleaner.
Re-tighten lug nuts to 147N.m. [ 108 ft-lb ] Revised wheel torque specs should be used anytime wheels are removed from the vehicle.


Lots of Bongo's with 18" alloys, any with 20"' ? I'd be interested to know what torque are they are all using? Naturally I have been worried about stretching the wheel nut threads at this high torque, but have not seen any evidence of this happening and I do not have any steering wheel shake which dogged me through the first year of ownership.

[Simon Jones]

Slightly worrying that sports car wheels can deform at low speed to the point of becoming loose.