Driveshaft CV Joint. Repack or replace?

[m3f_enderw88]

I think I have traced a driveline rumble to my aft CV joint. The boot looks great, but the joint is drier that I would expect. How much backlash should there be in that joint? There is more than I expected, but I may be out of calibration. I may just repack it.

[m3f_Roland H]

Shouldn't be any backlash in the joint. Use this opportunity to upgrade to a non-cv shaft, those CV joints don't last long at all.

[m3f_enderw88]

Shouldn't be any backlash in the joint. Use this opportunity to upgrade to a non-cv shaft, those CV joints don't last long at all.

too many dependencies: 6SP swap requires shorter driveshaft, 95 Diff has 6 bolt input etc. etc...I doubt I will cause another CV joint failure in the next several years...

[m3f_Roland H]

too many dependencies: 6SP swap requires shorter driveshaft, 95 Diff has 6 bolt input etc. etc...I doubt I will cause another CV joint failure in the next several years...

Just get a 6 speed driveshaft and a 4 bolt input flange, or an automatic M3 driveshaft with a 4 bolt flange.



You can convert now, or later, but sometime you'll have to do it.

[m3f_enderw88]

Just get a 6 speed driveshaft and a 4 bolt input flange, or an automatic M3 driveshaft with a 4 bolt flange.



You can convert now, or later, but sometime you'll have to do it.

I know, I know, but changing the input flange is such a PITA...

[m3f_englishtom1596q]

I know, I know, but changing the input flange is such a PITA...

i didn't think it was that bad to do? just pull the old one off and put the new one on with the correct torque spec?



Someone in the for sale section selling axles under the thread "FS: E36 M3 Parts Galore with Pics!"



Just out of curiosity, what kind of symptoms were you feeling?

[m3f_enderw88]

i didn't think it was that bad to do? just pull the old one off and put the new one on with the correct torque spec?

Unless I am missing something, the "correct torque spec" is set by tightening against the crush sleeve until you get a set amount of running torque. Replacing the input flange should require a new crush sleeve and should be done with the half shafts disconnected from the final drive. This is much harder than replacing a CV joint that will likely last at least another 60-80K...

Just out of curiosity, what kind of symptoms were you feeling?

I felt a rumbling when on heavy throttle or hard engine braking. It goes away if I am coasting or lightly accelerating/decelerating. At parking lot speeds with the car cold I could sometimes hear that ringing sound the driveshaft makes when something knocks on it. I pulled the driveshaft yesterday and there is probably 0.10 backlash measured at the periphery of the CV joint. The U-Joint is solid.

[m3f_hencini]

Unless I am missing something, the "correct torque spec" is set by tightening against the crush sleeve until you get a set amount of running torque. Replacing the input flange should require a new crush sleeve and should be done with the half shafts disconnected from the final drive.

If you're doing it with the diff in the car, yes it will be a hassle. I think the procedure involves spinning the input with an inch-pound torque wrench and I don't think there's room under there to make a complete rotation. If you had the diff out and on a bench, though, no big deal.

[m3f_enderw88]

If you're doing it with the diff in the car, yes it will be a hassle. I think the procedure involves spinning the input with an inch-pound torque wrench and I don't think there's room under there to make a complete rotation. If you had the diff out and on a bench, though, no big deal.

Yes, that is what I think is required as well. That makes it into a PITA.

[m3f_englishtom1596q]

I felt a rumbling when on heavy throttle or hard engine braking. It goes away if I am coasting or lightly accelerating/decelerating. At parking lot speeds with the car cold I could sometimes hear that ringing sound the driveshaft makes when something knocks on it. I pulled the driveshaft yesterday and there is probably 0.10 backlash measured at the periphery of the CV joint. The U-Joint is solid.

hmm maybe thats my issue because i have similar symptoms from the rear end on my car. driveshaft and CSB all seem fine but under deceleration i get a kind of a shuddering for about 3 seconds after i let off the gas from highway speeds. I figured it was an out of balance drive shaft but maybe not. Car does have 155K on it, i guess i'll add this to the spring list..

[m3f_Jrrrrrrr]

Yes, that is what I think is required as well. That makes it into a PITA.

You do need to preload the retaining nut over the crush washer as described. Not only is that a PITA compared to just working on the driveshaft, it is an expensive mistake if you get it wrong, as the longevity of the differential's pinion bearings is then significantly reduced.

[m3f_englishtom1596q]

anybody got a write up on how to do it? just for the sake of an evening read? I've watched videos on GM rear ends but on our car would be more beneficial.

[m3f_EricSMG]

I can almost guarantee that your CV is, at least partly, causing your "under load" vibes. I had identical symptoms and also had backlash in the CV. New DS and problem solved.



Looking back I should've just replaced the CV, CSB and Guibo and saved a few bucks. You'll need a rebalance, though.

[m3f_englishtom1596q]

I can almost guarantee that your CV is, at least partly, causing your "under load" vibes. I had identical symptoms and also had backlash in the CV. New DS and problem solved.



Looking back I should've just replaced the CV, CSB and Guibo and saved a few bucks. You'll need a rebalance, though.

well i got a set of axles free with some rear trailing arms i picked up so i guess i'll rebuild those and try them first. I would really like to not bite the bullet on a new DS if possible.

[m3f_EricSMG]

I hear ya man, that shit ain't cheap. BUT - TMS sells rebuilt shafts that ditch the CV for like $550 (no guibo, though) or so. New u-joints, new CSB.



I need to rebuild my axles too. There's a little looseness there as well. Freakin' old cars....