Smaller tires causing steering wheel shakes Options

[rocketcost]

Hey guys,

So I bought some low pros and alloys to put on my car, and at high speeds the steering wheel will shake. It comes and goes as I drive straight down the freeway. The difference in diameter from the OEM ones are about 1 inch smaller now. I have had the tires/rims balanced twice, the second time they said that both fronts were out about a half a gram. The problem still happens, so I called them again today, and the guy said that due to the difference in circumference, "the drive line is working harder" therefore causing the steering shake. To give you some numbers:
OEM (equivalent) according to google: 185/70 14
Current: 205/40 17

Difference between the two:
1.3 inches in dia.
2.3 inches in circumference
27 extra revs per mile

Is this pure bologna or are they telling me the truth (and I just don't want to admit these tires won't work)

Thanks!!

[ninentynineGT]

Try and find a place that uses a Road Force balancer, it doesn't just balance the wheel and tire assembly but also takes in account the force of road on the wheels and recommend the best position for each wheel to be put back on the car to minimize vibrations. It works. We just did it on a 2016 M3 today, only had 7000 miles but was getting shaking at 80 mph. We Road Forced his tires and were able to get it driving smooth like glass all the way to 120 no problems