I was having a vibration problem on my Toyota 4Runner even after having the suspension inspected as well as the steering. It would sometimes become a major vibration/wobble at the steering wheel.
I was baffled until I swapped the wheels over to my 'summer' tires and wheels. First my wife reported on a longer run that the wobble was no longer there. It was not until I went to clean and store my original coated alloys that I discovered that on one rim the lugnut holes were deformed and oval. The Toyota lugnuts are different to the cone shaped location on Volvo rims and lug bolts. The have a cylinder shape that fits into parallel sided holes and a very small chamfer. I could see if you are not careful fitting the lugnuts you could damage the holes in the rims, especially using the air ratchets.
I have done some reviewing of this issue on line and found many references on this subject that the temperatures that alloy wheels are held at while the powder coating can be at or above the temperature that softens the alloy. That would tie in with what I have seen in the before and after coating tire install on the rear of the rims.
Hm, maybe painting is better depending on what temperature they dry those at and for how long! Apparently temperatures as low as 325C can cause issues. One of the large wheel manufacturers in Italy voids any warranty if you powder coat their rims.
Makes you think!
Neil.
