I recently sold my summer wheels and put my stock winter wheels back on. Ever since then I have been getting this very strange vibration when I'm on the highway. Two of the stock wheels have bends in them and I had a friend rebalance them over the summer for me. He said that two of them were pretty much perfect and two of them were off balance a little.

Here's the problem:
When I'm on the highway and I turn the wheels slightly to the right, changing lanes, etc. I get this pretty severe shake, almost a wobble, in what seems to the the right front tire. It doesn't happen all the time, and occasionally happens when turning left. I jacked up that side and loosened the lug bolts then retightened them but that didn't help.

All lug bolts are tight, tire pressure is fine, it doesn't look like the rim is bent, on the outside at least.

What could be the cause of this? Bad balance on the wheel, something wrong with the tire? It becomes more evident at higher speeds, anything over 60mph or so.

There are several factors that can contribute to this, including out of balance or out of round wheels in the front, worn suspension components, or improper alignment. The first thing I'd do would be to make sure that the bent wheels aren't on the front. Then I'd inspect the front suspension for worn components (and repair as necessary). Once the front suspension is known to be in good shape an alignment (per BMW's procedure) would be a good idea.

At first I thought it might me suspension related but the car was perfectly fine a week ago when I had my summer wheels on. This just started occuring once I swapped back to my stock wheels so I think it must be related to them. I'm going to try and change that rim with one of the ones on the back and see how that goes.

I went to a shop and had them balance my wheels for me again. I know that two of them have dents in them so I said to put the two best ones on the front. They said they wheels balanced out fine and they put the two best on the front but I'm still getting this shaking.

I assume it could be suspension related but the problem just started once I swapped wheels. What could be causing this and what else can I check. It almost feels as if the wheels wobbles back and forth. It's not noticeable at slower speeds but at highway speeds is becomes very noticeable. It just happens when turning slightly, while changing lanes, etc.

Otherwise the car coasts perfectly smooth with no vibration in the steering wheel at all. Anymore thoughts on this?

A BMW suspension is extremely sensitive to out of round or out of balance conditions. This sensitivity is much worse if there's appreciable wear in the suspension components. Without getting the car on a lift and throughly checking the suspension parts you could have worn components and just not know it, particulary control/thrust arm bushings. Soft front struts will also make the car much more sensitive to wheel/tire issues.

It is possible that your suspension is fine and that you have a problem with the rims or tires. The only meaningful way to check the rims is to dismount the tire and check the rim for radial and axial runout, preferably with the rim mounted on the wheel hub. If the rims check out fine you have to consider the tires as suspect.

From the way the question is phrased it sounds like these rims are OEM, in which case the fit of the rim to the centering ring of the hub should be fine. I've seen aftermarket wheels whose fit to the hub was loose (~0.015") cause this sort of problem. The wheel would balance perfectly off the car, but wouldm't wind up exactly centered on the hub and there's be noticable vibration in the steering wheel.

Yes, the rims on there now are the OEM 16" sport package rims that came on the E36's.

The car has 105k miles on it and the front suspension has never been touched, is this when parts start needing replacement. I'm looking to sell the car soon and want to get it up to par before putting it on the market.

The only reason I'm not leaning towards a suspension problem is that I didn't have this problem when I had my aftermarket wheels on two weeks ago. But, I guess anything is possible.

Under most driving conditions I'd expect the front struts to be pretty badly worn by 105k. If the roads you drive are less than smooth the struts could be worn pretty badly. That'll make any wheel/tire problem much more noticable.

That said, it still could be a problem with these wheels and/or tires. The fact that it appeared when these wheels were mounted makes them a likely cause.

I'd suggest having the suspension professionally inspected by a shop with lots of BMW experience. If they don't find any problems you can be pretty sure it is the tires/wheels.

The car has 105k miles on it and the front suspension has never been touched, is this when parts start needing replacement.

Yes.

My recommendation is to swap the wheels back and see if the problem goes away. That way you won't be guessing if it's wheels or car.

I wouldn't expect a normally worn suspension to act that way. A damaged suspension might, though. For example, if the rear lower lateral control arms are bent, the car will feel unstable in turns. Unwitting tow truck drivers damage them frequently by hooking chains to them. Or perhaps they were used to jack up the car.

Apart from something being bent, loose wheel bearings are strong suspects.

I would swap wheels to see if the problem goes away but I went back to stock because I sold my aftermarket wheels.

The car hasn't been towed since I have owned it and I used the BMW supplised jack to change the tires.

I guess I'm going to have to bring it somewhere to get it looked at. I wasn't looking to dump any money into since it will be for sale soon, but I guess i have no choice in this matter.

If it's not he tires would it be worth getting the bent rims fixed? I have the full size spare that I could use. The tires on it is pretty shot, but I thought about having them put one of the 4 good tires on the spare rim and keeping one of the bent ones as the spare.

Moving a bent wheel to the spare position would be agood idea.

Well, according to the guys at the shop this morning the two best wheels are on the front. It seems like the right front wheel is the only one giving me problems.

I guess I'll have the tire off that rim swapped with spare. Thanks for the help you're giving me.

it's the bends in your rims - no amount of balancing is gonna make them ride true