E30: Driveshaft to differential bolts

[orangechicken]

Heading into Day 3 of trying to get the subframe dropped so I can do what I originally had planned to do (R&R subframe bushings and RTABS… wanted to do them with as little effort as possible and boy has that backfired…)

I was hoping to at least finished before I go to bed, but it's 3am PST now and I'm beat (worked on it 18 hours today, including several commutes to HF, Ace, etc).

My last hang-up get things dropped is the four bolts on the differential's input flange: I got the nuts off easily enough but are the "special bolts" supposed to come out, too? Because they ain't movin'…

I have not unbolted the CSB carrier yet which I'm guessing would block the universal joint from clearing the subframe tunnel, so I'm going to try that in the morning. If I just unbolt the CSB carrier – but not unbolt the driveshaft from the CSB – I should be able to get the universal joint out of the subframe tunnel by bending the driveshaft at the CSB, right?

I'm a week back into E30s after a 15-year hiatus and this job has had everything go wrong that could go wrong short of the car catching fire. Hoping tomorrow is brighter.

Thanks in advance!

[orangechicken]

Well that went poorly.

Got the subframe off now, but pulled the CSB off the splines in the process. I hadn't marked it (because I wasn't doing anything with the CSB… or so I thought). Crossing my fingers that nothing rotated in the process, but I marked it up immediately.

Problem is, now I can't get the CSB to go back on the splines. FML :curse:

So what's the trick there? Banging on the back of the driveshaft (in frustration) didn't budge it.

[orangechicken]

Oh, and it's a driveshaft from an E36 M3 (1991 318 S52 swap)

[36brua]

Don't bang on anything! Are you familiar w/ the 2 pc driveshaft ? If you separated the front/rear sections not too big of a deal. unthread/remove the coupling sleeve from the female end of d'shaft, slide it over the male splines then slip male/female splines back together. leave the coupler 'loose' fit driveshaft at trans and diff tighten sleeve, preload CSB. be sure the u joints are oriented correctly they should pivot on the same plain not 90* to each other.
The CSB is retained on the driveshaft with a circlip. did you force it out of the groove ?
Do you have a Bentley Manual ? GL

[orangechicken]

I have a Bentley for the E30 (which covers the body and suspension of my car). I need to get one (or find my old) for the E36 (which covers my drivetrain except for the diff which is from an E28).

I eventually learned about the coupling sleeve, loosened it, slid it over the splines and tried to rethread the splines. It wouldn't budge past the first 1/2" or so by hand… it needed some stern talking to. By a mallet.

Day 3 of my "4-hour job" replacing subframe bushings and RTABs ended OK though it was another brutal 18 hours (putting the total at 48…), and this time I had a couple friends for parts of the day! We got everything replaced and mounted back up. Just have to bleed the brakes in the morning and torque some bits to spec. I'm, unfortunately, quite unconfident and nervous to drive it… Fingers crossed!

Most important lesson I learned: buy/rent/borrow the special tools! Second most important lesson: I'm apparently not a master mechanic…

I think the last person who changed the CSB maybe put it in backwards… Is that even possible? The carrier itself is manufactured offset from center and it seems that the way mine is currently installed has the offset on the wrong side. Or maybe it's the transmission. Either way, it doesn't seem like the driveshaft is totally straight from transmission through the CSB to the rear end. Maybe that's the source of the "rumble strip" when under hard acceleration in 1st and 2nd? Both the CSB and the giubo appear to be in good condition with no signs of wear.

[36brua]

Depends on yr of chassis early chassis use an offset CSB so if installed backwards the driveline angle is screwed up .'Late chassis CSB are symmetrical and can be 'put on backwards' but not the early offset CSB. Install in stk orientation when using the E36 M3 driveshaft to maintain alignment CSB used generally matches year of car.
I'm definitely not a master mechanic either I understand how 4hrs = 24 been there

[orangechicken]

This is a bit of a franken-car. '91 E30 318i chassis, '99 E36 M3 engine/tranny/driveshaft, unknown year E28 LSD. The CSB installed on the car is definitely offset, and it appears to be offset in the opposite direction of the way the diff is offset. I'm guessing that it's backwards and that might be causing the vibration under acceleration in 1st and 2nd.

I think I might want to take the driveshaft off and get it rebalanced anyway (after it pulled apart with markings… even though I believe it didn't rotate at all and I marked it afterward).