Just broke my third driveshaft center support bearing

[JGood]

I cannot even describe how pissed off I am right now.

Anyway,

I did a five speed swap like 2 years ago, with a new CSB from bavauto. It broke a year later. I replaced it with a cheap one from some aftermarket company. It broke in like 6 months. I replaced that one with one from the dealer. Well, tonight it broke. Every time, the outer ring snaps at the weld and it lets it flop all over and break the transmission output flange.

I have a new guibo, all new hardware for the driveshaft, and the car is solid.

What the hell is causing this?

This is the worst week of my life, so I brought the e30 out to drive and relieve some stress. .8 miles down the road the driveshaft starts bouncin off the trans tunnel. Now I'm drinkin myself to sleep, hopefully one of you knowledgable people have some good news for me in the morning!

[JasonC]

Mine did this also. I'm on my 2ed one. When i bought the car it needed one so i replaced it and it went out in 6 months. So this 2ed one i put in i put a ( its kind of hard to explain ) bracket that encased the CSB. It's kind of a pain to change the bearing and when i did it last i smashed my thumb. i went to work the next day and the thing was throbin so i drilled a hole in my nail to releave the pressure. A week later the nail finaly fell off. I hope it don't go out again, cause it's not a job i like doing.

[trent]

I cannot even describe how pissed off I am right now.

Anyway,

I did a five speed swap like 2 years ago, with a new CSB from bavauto. It broke a year later. I replaced it with a cheap one from some aftermarket company. It broke in like 6 months. I replaced that one with one from the dealer. Well, tonight it broke. Every time, the outer ring snaps at the weld and it lets it flop all over and break the transmission output flange.

I have a new guibo, all new hardware for the driveshaft, and the car is solid.

What the hell is causing this?

This is the worst week of my life, so I brought the e30 out to drive and relieve some stress. .8 miles down the road the driveshaft starts bouncin off the trans tunnel. Now I'm drinkin myself to sleep, hopefully one of you knowledgable people have some good news for me in the morning!

I would put money down that the harmonic balancer on the front of your engine has gone bad. I have seen this many many times. Replace the front harmonic balancer with NEW (IIRC they are around $350), and you should be fine.

I am one of the knowledgeable people, and have seen this on about half a dozen E30s.

[jlevie]

The harmonic balancer is certainly a possibility, but I'd also be suspicious of the u-joints in the driveshaft. Especially if the 5-speed conversion employed a used driveshaft.

[JasonC]

if the harmonic balancer was bad, wouldn't it beat the main barings up and cause the motor to have a vibration?

[tonytony]

trent's talking about the drive shaft harmonic balancer

[ptownTSI]

trent's talking about the drive shaft harmonic balancer

i dont' think he is, he said on the front of the engine... don't most people toss that drive shaft harmonic balancer anyways?

[tonytony]

hmmm i own that bad, i just skimmed through it

[ptownTSI]

i think you might need a driveshaft rebuild. i don't know what else would chew up a CSB, maybe bad rear end bushigns allowing it to flow around more than it should. how are you tranny bushigns?

[Mot]

another Pnw member experienced this same problem, we ended up checking every part of the driveline. Check all the way from the back of the block to the diff. The diff bushing can go bad and cause somewhat similar ptoblems. Also check the harmonic balancer and make sure you preload the csb correcly.

[JGood]

Thank you all for your help everyone. I have a spare DS with a decent CSB from a parts car I'm going to put in today.

I upgraded diff's throughout this time period so that most likely isn't the problem. If it's the front harmonic balancer, that's too bad, it's not getting replaced. I will not spend $350 on a 220,000 mile ETA engine. I'll just swap in a used 2.5 for an extra couple bucks.

I guess we'll see what happens when I put this one in....

Thanks again.

[trent]

if the harmonic balancer was bad, wouldn't it beat the main barings up and cause the motor to have a vibration?

Yes, but no in this case.

[trent]

i think you might need a driveshaft rebuild. i don't know what else would chew up a CSB, maybe bad rear end bushigns allowing it to flow around more than it should. how are you tranny bushigns?

Doubt it. Problem will happen again.

[e30 gangsta]

unbalanced driveshaft was my case. 5 csb's in i swapped my shaft now its perfect

[JGood]

Well, I just put in a 112k mile shaft and it is sooo smooth. I think my shaft was out of balance this whole time, as my car has never been this smooth.

I snapped my rusty exhaust at the downpipes when I removed it, and when we welded it back together it took care of my loud exhaust leak. It's like driving a new car! So quiet and smooth!

Hopefully it stays this way for a little while.

Thanks for all your help guys, I really appreciate it!

Justin