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View Full Version : please help. strange front end problem



infurno
08-13-2007, 03:04 PM
Well i thought i was going to get a chance to take the car to bmw to get diagnosed today but that didn't end up happening. I scheduled an appointment for Thursday but if there is any chance i can get parts here by Saturday i have to order very soon. My classes start in a week and my car is not ready.

I have been working on this for a week, searching every forum i could find for clues. It seems like im the only one to ever have this problem, and on top of that its difficult to describe it.

I suppose i should start where this all began: Changed my thrust arms, tie rods, and 1 of the lower control arms. I could not get to the driver side control arm because one of the bolts on the boot is stripped. The driver side wheel is in fact loose, when i pull on it with my hands it moves around. I understand this is a problem and i have been working on getting to that lower control arm.

The problem:
1) at 40+ mph there is a humming sound, like the tire is rubbing on some part of the car. The sound does not change noticeably with turns but it increases at speed. When i took the wheels off, there was some wear on both my shocks. Like the tire is rubbing on the shocks. Which would explain the sound. I thought that since the tires are worn toward the car and i have replaced the worn front end parts i just need to put some good tires on. I swapped tires with my rear (more or less new. no strange wear) and the sound is still there. (though a little quieter)

Here is where it gets squirley. When i hit the breaks (not too hard, but enough to throw you forward a bit) OR i turn violently in a direction the alignment on the wheels changes. my steering wheel is thrown off center by maybe 20 degrees. The car yanks to the left. But the wheel noise is gone, and the car drives very well like absolutely nothing is wrong. but in this condition on turns the tires make noises. (not severe turns but no too light) its a very strange sound, but its defiantly the tire and how its interacting with the ground. not flat out squeal.

2) there is a knocking sound like a loose ball joint. (in fact there is a loose ball joint, remember my driver side lower control arm was not replaced)

3) generally just feel unstable and pulls to the left when breaks are applied.

Finally. Before i started the repairs, the car had a bit of a shimmy to it. Not a vibration but it would suddenly yank to the left. Its similar to what i described in (1) but it never made any kind of noise.

I had alignment done right after i changed the front end parts.

I understand that the first thing i need to do is replace that lower control arm. I have been working all day on locating a 46mm socket to get the bearings assembly off to reach the lower control arm. My other plan is taking some kind of power grinder to the bolt and remove the rounded head completely so i can remove the boot.

I would really appreciate any advice. Am i missing something? How could the tire rub on the shock? And then suddenly everything be fine?

Blitzkrieg Bob
08-13-2007, 03:12 PM
just take the three bolts off the bottom of the knuckle flange and you can access the arm nuts with ease.

infurno
08-13-2007, 03:18 PM
just take the three bolts off the bottom of the knuckle flange and you can access the arm nuts with ease.

I said boot but i guess i really meant the knuckle, sorry. One of the three bolts is stuck, completely seized. I spent days on it trying everything (except for heat, stupid me. i should have done that but its too late now) I cant get the knuckle off because of that bolt. Ill replace the entire shock if i have to but ill get that damn thing off. Im going to first try to grind the bolt head down completely with some type of hand-held power or air grinder.