Vibration above 30 MPH, violent Steering wheel wobble

[Synapse120]

I have a problem with my 325is, bought the car it was not running needed a radiator. replaced the radiator no problems engine stays cool, so now its time for a test drive. Car has 18inch rims and has been lowered. Engine very strong, sounds good, now on to the problem.

When driving at low speeds like 25mph, and below the car does seem to pull right, when getting above 30 mph the car shakes, and the steering wheel seems to wobble, turning left and right on its own. the shaking gets worse as the speed increases. Under braking the shaking will go away.

What could the problem be? I am thinking brakes are a possibility, also an alignment would be in order, and wheel balance, however the tires are fairly new probably 300 miles on them. My other thoughts are possibly motor mounts. This is my first BMW so looking for some expert advice on where to start.

Thanks,

[RNeil]

I had the wobble problem. It was due to a broken tire belt. Sorry to say, it can happen on a tire with 300 miles on it.

The pulling to one side issue sounds like alignment.

[Maverick1225]

May sound simple, but make sure the lug nuts are on tightly. Go ahead and do a quick check to make sure.

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I will definatly check the lugs, if i have to change the LCA & LCAB's, is there something i should take into consideration since the car is lowered?

Also how would i from home be able to check for a bad belt in a tire?

Thanks for all your help, this forum is awesome!

well i jacked the front of the car up, inspected the tires, and sure enough the passenger tire on the inside of the tire had some indentations on the sidewall right near the rim. looks almost like the tire is pulling away from the rim inward. I would imagine this is broken belt, any confirmations would be helpful.

I also grabbed the LCA(Lower Control Arm) near the LCA bushing, and i am able to move the arm from side to side and up and down. The ball joints and tie rods look ok and there is no play from those connections that i can feel. Should i replace everything or just the LCAB on both sides?

Thanks again for the help and advice.

[bmwdirtracer]

You need new tires, and I highly recommend selling the wheels, and putting some air between the metal and the road- seventeens are much better for road use.

You should certainly consider buying control arms, with ball joints included, since your cabs are so badly trashed.

Your entire lowered suspension should be thoroughly checked by a BMW pro or techie-type! If stock shocks were used, they're toast. If camber wasn't corrected, you'll eat tires like crazy, and handling will be greatly diminished, rather than improved, by the lowering.

[Synapse120]

Inspection of the shocks they appear to be aftermarket, The tires were definatly shot, and according to the tire shop running the wrong size for that car, tires on there were 225/35r18 and the car should be running 235/40r18. I am replacing all 4 tires with the correct size for the wheels i have(cant afford wheels and tires this month ), and will have the suspension professionally inspected. I have the factory spare on the front right now, and the car runs true, and no violent wobble/shake.

Thanks for everything, great advice