advice on a recently aquired e36: tires, brakes, etc...

merl77 · 10-14-2002, 01:43 AM

hey,
hot damn was i happy to find this post!!

so here's the deal:
two days ago i bought a 92 325i with 165,000 miles. This is my fourth bimmer, so the high miles did not really freak me out (before this i had a e30 IS with 165,000, but it was killed by a deer!). The car is super clean and has had what i believe to be all the problem parts (radiator, waterpump, themostat) replaced. Am I missing anything there?
The car does have two problems:
1) at speed, braking causes a pronounced wobble and shake. Normally I would think this was warped front rotors, but they were replaced 10,000 miles ago. could they already be warped again? (they are OEM replacements)
2) There is a "loose" feeling in the front of the car, which i believed to be bad lower control arm bushings. After doing some research on the web, I realized that it may also be the ball joints. Is it necessary to replace the whole control arm in order to replace the ball joints ( i have heard conflicting stories on this issue). Regardless, I am definitely going to replace the bushing and go urethane ( I did this on my e30 325is and it made a tremendous difference). When I do this should I use centered or offset bushings? What is the difference there?
Finally, I think I will get new tires...anyone have an opinion on the yoko avs VS. the db's? I live in Portland, OR so it's going to be raining for the next few months...
ok, here i go to order the bentley manual!
thanks in advance for the help.
Merlin

Wayne 962 · Wayne 962's Garage

Sweet - welcome to the club. I have a 1992 318is, and a 1993 325is.

How's the head gasket? Mine took a dump recently, and the head is coming off for repair...

Warped rotors are easy to check. Also may be your tires too (not likely, but possible). Could also be the front wheel bearings. Lift the car off of the ground and wiggle the wheel back and forth to see if it wobbles.

You can also check the runout (warpedness of the rotors) really easy by spinning them freely against a dial indicator.

You talk about the looseness of the front suspension? I suspect it may be related to your wobbling when you're braking. If the front suspension components/bushings haven't been replaced, now would be a good time to start. Yes, you basically need to replace the whole arm to replace the ball joints. The arms aren't that pricey though...

What do you mean by centered / offset? I haven't heard of that before?

Tires, hmmm, I'm not an expert, but the Yokohamas are known for their high quality...

-Wayne

stupenal · 10-14-2002, 11:46 AM

Im not technically inclined, but I also have a 1992 325 with high mileage (154k to be exact). Yes, ball joints LOVE to give out....i think mine are pretty much shot. I'm going in to the mech soon to fix it. The only real help I can give you is my personal experience with tires. I'm not so sure if tirerack.com is still selling the Yokohama AVS intermediates, but they were selling them FOR CHEAP!!! Yokohama discontinued these tires, but tirerack still had the stock size in stock (205/60/15). They were going for $47......CANT BEAT THAT WITH A BASEBALL BAT!!! With new tires (old ones were really crapped out), the car felt completely different. I have yet to corner so hard as to cause the tires to squeal. However, for rainy weather, they aren't exactly the best.

The dBs were regarded highly by many, including Car and Driver and mr. Blackfoot (he hangs out in the 944 board). My AVS intermediates are pretty quiet, but I heard they get pretty loud as it wears down. The dB are also decently priced ($67 IIRC) and give good performance. With the RWD setup, I'd go with tires that are given a VERY HIGH wet traction rating. Just making simple right turns in wet conditions can send the rear crazy!

JasonBMW · 10-14-2002, 12:12 PM

Most tire shops will match TireRack's prices - I find it easier just to make the trip down to the tire shop...

merl77 · 10-14-2002, 12:35 PM

wayne-

the bushings come with the hole in the middle either centered or offset. bavarian autosport descibes them as "Bavarian Autosport Control Arm Bushings - Pair - Urethane - offset for additional caster". I think this may be the way they come on the M3. does anyone have a thought on this?
More questions:
Do you mean that if the wheels wiggle back and forth when the car is in the air, that that is that a sign of bad wheel bearings?
Is there a way to check the condition of the head gasket, or is that just something you have to wait for to see if it goes bad?
thanks!

JasonBMW · 10-14-2002, 12:39 PM

Oh, that makes sense - I was wondering about that as well. You want to be able to tune your caster for racing apps.

Lift the car up in the air, and compare all four wheels when you wiggle them back and forth. Typically, if a wheel bearing is going bad, you will find one wheel that wobbles quite a bit more than the others. A little bit of wobble is okay. Any real noticeable amount is bad. This is something that is difficult to describe in a post.

Head gasket ? As long as the car had the radiator fluid changed and flushed regularly (once every two years or so), then you shouldn't have a problem. Deposits can build up inside, clog the water passages, and make the water leak out of the head.

Wayne 962 · Wayne 962's Garage

Yeah - what he said

Another thought - if the owner used water instead of anti-freeze, then that is pretty bad as well, as all of that stuff in drinking water (the stuff that collects on your shower door) will collect in your engine...

-Wayne

Dave at Pelican Parts · Dave at Pelican Parts's Garage

On most cars, you check the front wheel bearings with the wheels on the ground. (Quick and dirty check, e.g. for autocross tech inspection.) Just grab the top of the tire and shove in and pull out. A little "click" feeling is just fine. A "clunk" feeling is a sign of a wheel bearing that needs attention.

Early-ish 911s and 914s have front wheel bearings that can loosen up with severe use (e.g., autocrossing for a couple of years). They can be re-tightened and things will usually be fine for months longer.

Bad ball joints, bad bearings, and other front suspension problems can contribute to wheel shake. The fact that it's under braking does tend to indicate warped rotors, but there is some possibility of other problems.

And yes, you can warp OEM rotors really quickly. A buddy of mine has an M3 of this vintage, and he warped new OEM rotors after a month. Of course, he was at Laguna Seca at the time... And Seca is a track that is known to be hard on brakes.

--DD

SuperWheel · 10-14-2002, 09:53 PM

Right - there are many posts on this BBS about vibrations caused by warped or bent rotors...