New CSB and Guibo or new driveshaft?

[ColonelMustard]

So my car started making significant thudding sounds coming from the rear when I accelerate from a dead stop. After I'm past 10-15mph it goes away. I also notice some vibrations at times too. I'm sure my CSB has given up the ghost. I know if the U-joints go bad the shaft bearing wears out quickly. In order to avoid destroying the new bearing and needing to do the repair twice, I wanted to make sure the u-joints aren't worn out.

How do you guys tell if the drive shaft needs to be replaced? Can I diagnose it prior to pulling it from the car?

It is my DD, so I can't have it down for too long.

[oliver.r]

you should probably take a look at the center support bearing first. in some extreme cases i have seen the rubber completely ditiriuorate and the drive shaft just resting on the bearing housing. that would cause clunking at very low speeds for sure

[SkiFree]

Yep, center support first. But yes, the u-joints do wear enough to warrant double checking. I'd also be looking at your guibo as well.

Here's a vid I took showing a bad u-joint on a 2002 driveshaft, given the e30 uses the same joint it should be pretty easy to cross-reference. To check the u-joint just grab either side and try and twist to check for play.

https://www.youtube.com/watch?v=gLlFkmKtxPQ

[ColonelMustard]

Thanks.

I already planned on replacing the guibo and shaft bearing. Then reading about it further, I started to worry about the u-joints. Sort of the equivalent of looking on webmd and realizing you have the symptoms to a dozen serious diseases.

That video was helpful, as were a string of others I checked out. I think my plan is to swap out the old CSB and guibo, and inspect the joint while in there. If it's bad, I guess I'll just have to do the repair twice. Most new drive shafts come with a new bearing anyway so if the new one gets eaten up it won't be the end of the world.

[lambo]

I'm in the same situation and I made the same decision. Replace flex disc and csb and see where it gets me.

[jlevie]

In almost all cases, a failure of the CSB will be caused by bad/binding drive shaft u-joints. Replacing the drive shaft with a reman (which usually comes with a new CSB) is the only long term fix.

[reelizmpro]

I'll second that. If you have the means, it's worth it to just get a reman'd driveshaft with everything already installed and balanced. You certainly don't want to change the CSB/guibo on a shaft with bad joints. Then you've just wasted a lot of time and money when the CSB's go bad and/or your U joint fails and you have to do the job over again.

[ColonelMustard]

Alright. So I'm convinced that I should go ahead a swap the entire driveshaft. I found someone selling one from a 325is with only 10000 miles on it for pretty cheap.

Will this drive shaft from a 1987 325is coupe work for my 1987 325 sedan?
Both are manual transmissions.

[hammrdwn510]

I went the cheap route (csb,guibo) and wish I would have just replaced the whole driveshaft vibrations started showing he selves about 2k miles after first repair. Car is down atm while saving my nickels for a new/reman ds. I got lucky and found a guy local to me on CL parting a 325i picked up the ds for 80 along with other parts I needed

You may want to consider changing your transmission mounts while you're at it. One was completely ripped from the trans.

[hammrdwn510]

I went the cheap route (csb,guibo) and wish I would have just replaced the whole driveshaft. Vibrations started showing themselves about 2k miles after first repair. Car is down atm while saving my nickels for a new/reman ds. I got lucky and found a guy local to me on CL parting a 325i, picked up the ds for 80 along with other parts I needed

You may want to consider changing your transmission mounts while you're at it. One was completely ripped from the trans.

I think the eta uses the bigger guibo than the i and is, keep that in mind
Cheapest I found remaned ds online was around $340+ 80 core but free shipping and return shipping of core

[ColonelMustard]

So to post an update.

I replaced the drive shaft with a re-manufactured one from Mesa Performance. The install went pretty smooth, without any major hang ups. Then I took it for a drive, and I thought I was feeling vibrations when I shouldn't. At first I thought it was "phantom vibrations" I was feeling simply because I was so focused on feeling for them. Then the next morning driving to work I was convinced something was amiss.

Since I was going out of town and didn't have time to crawl under it again I brought it to the shop to fix whatever I had done wrong. After leaving my car with him all day, he tells me everything was installed correctly and it is engine vibrations translating into the DS.

I think its strange it would develop this vibration right after replacing the DS, so I'm a little stumped. I changed the trans mounts with oem replacements, but I wouldn't think that would be the cause. The vibration is RPM related and not speed so I know its not the DS. I can rev it in neutral and feel the engine shake.

I'm going to test the compression and see if one is way off of the others. Anyone have any thoughts?

[B1mmer]

Did you replace the flex disc? If so, was it installed in the correct direction? I bought my from Driveshaft Specialist of Texas. They use the stock style non-servicable staked u-joints. While that doesn't sound like something you would want, I went with them because the stock one's last a long time and I've heard issues with serviceable joints. Does this unit have serviceable joints? - AB