I've done a search on this issue but I think my issue is a bit more specific than the posts I've read. I have the car now for almost 2 weeks and specifically at 60mph the wheel vibrates and if I press on it smooths out at 70mph and beyond. I thought of wheel balancing, but if its smooths out, could it be engine mounts? The car has 105K on, but it has the mounts replaced twice so far.
The car also came with Pirelli Snowsport 210 tires on which I'm not thrilled with anyway but given my inexperience with snow tires, could that be a factor too?

Thanks in advance;

Danny

 

No expert here, but I'd start with the tires and wheels. Have them professionally checked and balanced.

If the problem was with engine mounts, I would think it would happen at more than one specific vehicle speed, as it would be based on engine RPM's. The vibration would show up at a specific RPM, so it would be different vehicle speeds as the transmission shifted up through the gears. If you feel a vibration at 60 mph in fourth gear, what are the engine RPM's? Now shift into third-gear and go to that exact same RPM (lower vehicle speed) that you felt the vibration at 60 mph in fourth gear: any vibrations?

 

Yeah! Good idea! DOH...why I did not think of this, I will try that for sure....thanks for the tip.

 

I've experienced both problems.

I had a set of Alessio rims on my car and would also get a wobble at 55, then fine at all other speeds. Had the rims balanced several times, but the problem was still there, drove me nuts. Replaced the rims with staggered 18" AMG's and the problem was gone. I thought the Alessio rims were bent, but now I am getting a really slight wobble again, which worries me. The wheel weights are still on the rims, but I'll probabkly have them balanced again to be sure, especially since they are stags.

I suggested to another member to maybe swap out rims for a day with another member, see if the problem is still there. A bent rim can be very difficult to detect.

On the motor mounts, there are several things you will notice. It starts with a kind of pop/clunk when you turn the ignition over; then you notice the car is louder while in gear (not so loud in park); and then it progresses to a full shake, rattle and roll. If you pop your hood and jump on the gas, you will see noticeable movement in the motor.

My motor mounts are wasted and I'm taking it to the stealership to have them replaced. I bought OEM mounts from them and thought it was a DIY project - but I couldn't get it done. Another guy said remove the air cond unit on one side; alternator on the other. Considering everything has specific torque tolerances, I said fawk, I give up.