Vibration while in 2nd gear ?

[Jean]

You do have to undo the csb to do the trans, so the shop may have put it on wrong.

Gotcha. I called the shop, going to see about having them inspect it and see what's wrong. $100 per hour :hitler: is their rate, they'll start at 1/2 hour.

[ivo316]

Wait a sec, I really don't know how this works in E30's, but in Muscle cars, if you mount the driveshaft (let's say) 25º off, or 180º off the way it was before, it will rattle your teeth because of balance issues, have them check the balance of the driveshaft, when unbalanced they usually vibrate at a very close rotation speed range.

This may have unbalanced the driveshaft/tranny (when looked at as a unit) what I'm triying to say is that maybe the driveshaft was compensating an imbalance or misalignment of the tranny, so when mounting the driveshaft off in xº the imbalance could be noticeable.

Have you checked if the car vibrates also at the same revs in third gear ?

PLease disregard if all this does not apply to E30's

Just my .

[Jean]

Wait a sec, I really don't know how this works in E30's, but in Muscle cars, if you mount the driveshaft (let's say) 25º off, or 180º off the way it was before, it will rattle your teeth because of balance issues, have them check the balance of the driveshaft, when unbalanced they usually vibrate at a very close rotation speed range.

This may have unbalanced the driveshaft/tranny (when looked at as a unit) what I'm triying to say is that maybe the driveshaft was compensating an imbalance or misalignment of the tranny, so when mounting the driveshaft off in xº the imbalance could be noticeable.

Have you checked if the car vibrates also at the same revs in third gear ?

PLease disregard if all this does not apply to E30's

Just my .

If I skip 2nd go from 1st to 3rd, it doesn't vibrate as much. But I don't know for sure if it's going through the exact same rpm range at a given mph like it does in 2nd.

[blunttech]

is the shop that did the work BMW knowledgeable? i bet they separated the d/s and its out of phase

[Jean]

is the shop that did the work BMW knowledgeable? i bet they separated the d/s and its out of phase

It's a bmw/mini performance shop, should be knowledgeable, all I had them do is replace the clutch, flywheel and tranny bushings. I don't want to blame anybody just, maybe I "shifted" the driveshaft just slightly when I replaced the rear diff. if that's possible but I never removed the driveshaft at all. I just jacked the car up to see what's up but w/o a lift it's a pain and I can't tell so it will have to wait until I get access to a lift.

[Jand3rson]

I assume you removed the driveshaft. when you reinstalled it, did you preload the CSB to the front 4-6mm? I killed 4 or 5 of them on various e30's by not doing that, but since I started doing that I've had no problems.

This is a point of contention from person to person. I didn't preload the CSB on the last 2 that I did, and never had a single issue. I've also talked to several other people, including Trent that have never done it. Since then, I've always told people that it's not required. The Bentley will tell you it is, but a tech at the dealership here told me he's never done it and never had any problems.

Ryan is right, the problem is most likely the u-joint(s). Driveline Service of Portland sells remanufactured driveshafts for BMWs with serviceable u-joints, but some people have had bad experiences with them, since the u-joints they use are Nissan pickup units. Most people I've talked to have had no issue with them, but there are always exceptions. The next easiest route is to try and find a low-mileage used shaft and have it rebalanced yourself.

[Jean]

If it's the driveshaft I am putting this car on hold, I don't want to deal with tranny/driveshaft twice. :(