[Blue Streak]

I'd like to hear some of your expert opinions about alignments. Here's the situation: I have a 2007 E90 335i (Aug 07). It currently has about 12k miles on it. Up until a certain point, the car has driven perfectly solid, straight and steady and the steering has been excellent. I'm not sure exactly what that certain point was, but for the past couple of months the steering and even straight line control has been way less than ideal, at any speed over about 30 mph. The wheel does not necessarily pull to the left or to the right, but it feels like it jerks around to either side of the center point, which makes controling the car much more difficult compared to the sold and steadiness that it used to have on flat surfaces and freeway cruising.

The 2 variables that I can think of are the fact that I added 12mm RE spacers to the rear wheels (didn't notice a difference in handling right after that). The second variable is that I got a slow leak in one of the rear tires soon afterward and I replaced both rear tires about 3 weeks after installing the spacers. The rear tires are NON-RFT Yokohama S-Drive of the exact same size. They are UHP as opposed to Max Performance (like the OEM Bridgestones that are still on the front).

I took it in for an alignment at a Firestone Complete Auto Care store about 2 weeks ago. Of course they can't add all those 150lb weights like the BMW instructions call for... I just want it to steer right again. The end results were printed on a form that they explained to me. It showed that all the wheels where out of the specified ranges, and one or two were more out of whack than others. So now they're all back within range. I drove the car after that and it definitely felt better, but it's still not "dialed in" or even close to how it used to be. It still feels like it jerks around on center. I'm thinking I either have to take it back in for another alignment check, or it might have something to do with the spacers on the rear wheels or the fact that the rear tires are non-runflat and the fronts are the stock run flats.

Any opinions?

Thanks.