Wheel Vibrations/Steering Wheel Shimmining after 50mph

[rb0135]

Hi All,

Long story but will try and cut it short. I have purchased some second hand 19" OEM rims, and had to buy two new tyres (two were already newish, so I got two new ones the same - Goodyear F1 Directional 5 - non staggered 255/50).

These wheels are replacing 20" OEM Rims.

Now, with the 17" rims that came with the car and the 20" I never ever had vibrations (like unbalanced wheels). I have put the 20"s on to test, still no vibration (but creates other issues, so we wont go there, hence the 19" wheels).

However, with the 19", any speed 50mph and over, I am getting a shake/shimming through the steering wheel like unbalanced wheels. Cant feel anything under 50mph and driving above 50mph just causes the vibration to get worse.

The mechanic suggested putting the older tyres on the back. Now the whole car vibrates over 50mph, to the point that I had my golf clubs in the back, and they rattle that much I had to slow down (you can feel the vibration in the seat, floor pan, etc) and similar to driving on a washboard road. Except the road did not have washboard surface and going over the same road testing with the 17" and 20" did not cause any vibrations.

Now, I hear you saying Thrust Arm Bushes, tie rods and that, but the mechanic has checked them out to be A1 and also putting the older tyres on the back causes all this vibration.

So, does it point to the older tyres. They have been put on a balancing machine and are balanced. Not sure what speed they balanced them at (two different shops).

Yes, I could go and buy two new tyres, but they are expensive, specially if they dont fix the issue.

Any ideas to check? Should I try to get the Tyre place to show me what happens on their balancing machine by spinning up to 50/60mph. Can a tyre have an issue above a certain speed (never happened to me before in 30+ years of driving). Anyone have similar issues with one size rims causing no vibrations and another size causing vibrations.

Any ideas greatly appreciated.

Thanks,
Rob

[upallnight]

Could be bent wheels. Thrust arm are normally a problem when you brake above 55 mph and you feel shaking in the steering wheel or at the pedal.

[SlickGT1]

2 Things, please update your sig with your car info, like year and model. Helps others help you easier.

I have a feeling your overall rolling diameter is off between the two sets of different tires. If your car is pre-facelift, your transfer case has a set torque split front to rear. Not sure if it allows for much slip caused by rolling diameter differences, but that is where I would start.

[upallnight]

Originally Posted by SlickGT1

2 Things, please update your sig with your car info, like year and model. Helps others help you easier.

I have a feeling your overall rolling diameter is off between the two sets of different tires. If your car is pre-facelift, your transfer case has a set torque split front to rear. Not sure if it allows for much slip caused by rolling diameter differences, but that is where I would start.

Great call if he brought different size tires or the old tires are worn enough to cause the difference in rolling diameter..

[Ricky Bobby]

what kind of balancing have you done? do you guys balance on road force machines Down Under?

[rb0135]

Thanks for all your replies

Could be bent wheels

That was the way I was thinking and hoping not. The only question I would have on that, is if it was a bent wheel, would you feel it at even 30-40mph?

I have a feeling your overall rolling diameter is off between the two sets of different tires. If your car is pre-facelift, your transfer case has a set torque split front to rear. Not sure if it allows for much slip caused by rolling diameter differences, but that is where I would start.

The two tyres that werent replaced were virtually brand new, but, you never know what life they have had. Mechanic states 98% tread left on them.. Mine is a facelifted '05.

what kind of balancing have you done? do you guys balance on road force machines Down Under?

Balanced twice with wheels off the car on a machine. Not sure what type machine. Not sure if it was a cone or finger clamp either.

Thanks,
Rob

[upallnight]

At 30-40 mph the wheels are spinning at a slower speed so depending on how bent the wheels are you may or not feel it. When they put the wheel on the balance machine can they spin the wheel slowly to see if it is bent? Most tire balance machine has a hood/cover that cover the tire so you will not be able to see the wheel spinning while they are balancing the wheel.

[rb0135]

Thanks all.

Well, I took it to the Tyre manufactures outlet who have a balancer that can check rims. They took the tyre off the rim, ran it on the balancer and found one out of two is out of round

They have verified the tyres to be fine.

So, of course it has to be that.. couldnt be a faulty tyre... arghhhh..

They say it's not that bad that it can be repaired without any ill effects.

Never had alloys repaired.

Any thoughts?

[SlickGT1]

If your car is '05, it's facelifted.

Sux in the rims. Not sure how a 5000lb car likes repaired rims. Let us know how that goes. Lol

[rb0135]

Originally Posted by SlickGT1

If your car is '05, it's facelifted.

Sux in the rims. Not sure how a 5000lb car likes repaired rims. Let us know how that goes. Lol

Thanks.. Sorry, I realised I said pre-faclifted, but I knew all along it is facelifted.. shouldnt type so fast and should check what I type.

I'll let you know how I go... it's pretty cheap to "repair" (compared to finding/buying a new rim) and the place that repairs them apparently design and manufacture custom alloy and steel rims. I'll let you know the process they use as well.

Rob