528i Gear Shift and Right Rear Shaking

E28 technical advice asked and given! Troubleshooting, modifications and more.
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AlessiRocks
Posts: 52
Joined: Sep 21, 2015 7:11 PM
Location: Baleares, Spain

528i Gear Shift and Right Rear Shaking

Post by AlessiRocks »

For a few months my gear stick has been vibrating in 1st and 2nd gear specially under acceleration. Also felt that shifting gears was getting more rough over a year but now it's not gotten worse in many months. Up from 3rd it seems there is a slight vibration but maybe nothing out of the ordinary, it's smooth overall. Now under semihard acceleration I can feel something in the rear right side of the car shaking/knocking but upon inspection I see nothing wrong.

No weird play in the axles and the boots are in good condition.

Diff has been leaking but it's nothing new, could low fluid level cause problems?

Driveshaft mounts were replaced 5 years ago together with the clutch but I haven't had a look at the center bearing. Transmissions mounts are ok and no bolts are loose. Maybe something needs adjusting?

The rear dog joints were replaced recently but I feel like the gear shifter was already vibrating before that, could the new joints just be too stiff?

I don't know where to look because I'm confused why my gear shift shakes and now my right rear shakes. Could it be low fluid levels? Something needing some grease? Maybe some loose bolt? If anyone has any idea why please let me know. My E28 is a 1986 528i. Thank you in advance!
Mike W.
Posts: 27180
Joined: Feb 12, 2006 12:00 PM
Location: California Whine Country

Re: 528i Gear Shift and Right Rear Shaking

Post by Mike W. »

I don't recall feeling or seeing it in the shift lever specifically, but vibration starting out in first and second gear can be caused by stiff driveshaft U joints. BMW U joints tend to get stiff and notchy with age, not loose. Also not enough forward loading of the driveshaft center support bearing can contribute to it. Some people have even glued a piece of fuel line into the pocket of the center support to try to stiffen it up.

Not saying that is the problem, but it might be.
AlessiRocks
Posts: 52
Joined: Sep 21, 2015 7:11 PM
Location: Baleares, Spain

Re: 528i Gear Shift and Right Rear Shaking

Post by AlessiRocks »

Gonna inspect the driveshaft closer tomorrow then. It doesn't do it as much as when starting out but in acceleration. I also realized that since the clutch change 5 years ago it had been not as smooth which now makes me think that when we replaced the driveshaft mounts/couplings or however they're called, I wasn't present in the moment, if someone had rotated the driveshaft out of the alignment it was in could that have created a problem?

Thank for you input as right now I'm kind of lost so anything I can poke around to check, I'm gonna check haha
Mike W.
Posts: 27180
Joined: Feb 12, 2006 12:00 PM
Location: California Whine Country

Re: 528i Gear Shift and Right Rear Shaking

Post by Mike W. »

And preload the center bearing as much as you can. It probably won't be much, but it can make a difference, it keeps the shaft from bouncing around as much.

The driveshaft is a bit of a pain, you have to pull it to try to rotate the U joints. And it's a notchness feel right on center, it'll be smooth, then get to the center and you feel a binding moving it off center. The problem is knowing how much is too much and unless it's been rebuilt with new joints they all have some notchy feel.
Federico
Posts: 567
Joined: Sep 16, 2013 6:38 PM
Location: Argentina / California

Re: 528i Gear Shift and Right Rear Shaking

Post by Federico »

I used to have a vibration/shudder under acceleration as you describe, and it turned out to be the driveshaft was assembled wrong:

https://www.mye28.com/viewtopic.php?f=3&t=159269


The joints were 90° off. The caps looked aligned, but the yoke welded to the main tube was not aligned with the yoke on the splined shaft.
AlessiRocks
Posts: 52
Joined: Sep 21, 2015 7:11 PM
Location: Baleares, Spain

Re: 528i Gear Shift and Right Rear Shaking

Post by AlessiRocks »

Haven't been active for a while but I want to give an answer to my initial post. Next week I will be finally dropping the driveshaft as well as the right half axle.

As far as I can visually see the driveshaft looks good and it wasn't dropped when we changed the clutch. From what I recall, when we changed the clutch, the guibos were replaced by first replacing the front then the rear as to not let the CB hold all the weight, should we have preloaded the CB after this? The car then drove 5 years until now with no vibrations.

Also will be droping the right half axle as I think that is the main culprit of these vibrations. Only under power do I feel a vibration on the stick or hear a sort of knocking noise from the right rear. Upon closer inspection I see there is a thick layer of very hard caked on grease on the right inner CV joint and a bit around the area. It seems that it has been like that for a long time so I don't know how I didn't see it. When checking for play by spinning the wheels some light clunking noise seems to come from the right inner CV joint. I feel like this is what I could be feeling on the gear shift before it starts to be a loud clunking under power. The gear shift feel and the noise under power have the same rythm it seems like but I can't know for sure.

On the bright side after all these years of power sliding at times, I can confirm my E28 came with a limited slip differential. Never checked to confirm and just enjoyed the fun.
AlessiRocks
Posts: 52
Joined: Sep 21, 2015 7:11 PM
Location: Baleares, Spain

Re: 528i Gear Shift and Right Rear Shaking

Post by AlessiRocks »

Update: After inspecting the driveshaft and CSB, I see no issues. I can't feel any play or anything strange. The CSB is in good conidition but it was not preloaded! I have now preloaded it and taken it for a test drive but the right rear shudder/vibration persists. I also checked that the shafts were clocked properly, there were 2 marks and they're aligned.

The gear stick now only vibrates in first gear and it's quite subtle, no vibration in the other gears. Is this normal?

The shudder/vibration comes for the right rear very clearly. It happens in the 2500-3000 rpm range when accelerating only then it stops. Next step is inspecting the half axles and CV joints. As a test I thought of switching the axles around and seeing if the vibration transfers to the other side. Is this a stupid idea and are they even swapable? I also checked if the wheel wobbles but it seems to be ok too. It spins normally so I doubt the bearing is an issue.

My last idea is that with the knowledge that my car has an LSD, could the oil have gone bad and is causing the clutches to slip?

Thank for any guidance! I am working on this issue slowly as I don't have much free time though I want to keep this post updated and hopefully give a solution for future reference.
AlessiRocks
Posts: 52
Joined: Sep 21, 2015 7:11 PM
Location: Baleares, Spain

Re: 528i Gear Shift and Right Rear Shaking

Post by AlessiRocks »

Took out the rear right axle. The inner CV joint has some play and makes noise, though I don't know how much play is normal. There is still grease and even though old it seems to not be too hard. I have attached a video and picture.

Video: https://www.youtube.com/watch?v=AI8v39QWnxs

Picture: https://imgur.com/a/Y7TD4ix

Edit: I swapped the half axles around and the problem is still there. I touched the transmission tunnel in the rear seats and now I can feel the vibration clearly coming from there instead. I touched exactly after the center console. When I took out the driveshaft it didn't feel wrong and any notchiness was barely perceptible. Am I looking for absolutely no notchiness?
AlessiRocks
Posts: 52
Joined: Sep 21, 2015 7:11 PM
Location: Baleares, Spain

Re: 528i Gear Shift and Right Rear Shaking

Post by AlessiRocks »

Took out the driveshaft to check everything another time. Somehow I missed to shredded and cracked guibo, the CSB looks good. The ujoints... I just can't tell if they are bad or not. They are not loose or tight, they move like they are on moon gravity. I can't feel any notchiness though I can feel an ever so very slight spot in the middle on both ujoints and only on one axis of each ujoint. The ujoints move smoothly other than that. I have no idea if this is bad or normal. There are no shops around me that work on driveshafts so I can't find any guidance locally. What are some key signs of a bad ujoint? The guibo definitely needs changed so might as well do the CSB too.

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