Collapsing/Separating Driveshaft

[capitoljake13]

Working on a Flex-disk and CSB replacement.

Dropped the exhaust
Removed Guibo bolts
Loosened the collar nut behind the CSB just a little bit
Removed the CSB bolts
...and here's where my question is.

In dropping the driveshaft from the transmission, I THINK that I performed what people call "collapsing" the driveshaft because the spline connecting the mid and rear sections is no longer visible. (Before removing I could see a good couple inches of the spline)

But, I'm not able to pull the mid off of the rear.... Did I just not loosen the collar nut enough? I probably only got a 3/4 turn on it (assuming I went the right way). But, if not then how did the spline "collapse". Or is this thing just a huge pain to pull out now matter how loose that collar nut is?

[jlevie]

If it hasn't been off in a good while the drive shaft may not want to collapse. Unscrew the collar nut and expose the junction of the two sections. Spray that liberally with PBlaster or Kroil and give it time to penetrate, like a day or two. Then see if you can collapse the drive shaft. If it still won't go by hand, remount the CSB and use a pry bar at either end.

After you get the drive shaft out make sure that the paint marks on the drive shaft are still visible and if they aren't make new ones so you can reassemble the drive shaft like it is now. Then separate the sections and clean and lubricate the splines with grease.

[capitoljake13]

Well that's what's messing with me. I think I DID get it collapsed because the spline that was once visible is no more. That's how I was able to unmount it from the transmission... It's just that now I can't get it to separate. One would think that if it were able to collapse, it would be able to separate.

Am I examining the threads of the collar nut correctly? Should I have been cranking it the other direction?

[jlevie]

I'm confused. Have you gotten the drive shaft out? If it is collapsed enough you can get one end off, either at the transmission or differential. Once that is done you can get the other end off and the drive shaft out.

[capitoljake13]

I shouldn't need to take the whole driveshaft out right? Just need to separate the middle and rear section to be able to change the center bearing. So far, I'm collapsed it enough that I got the front section separated from the transmission... But, haven't been and to "un-collapse" it and separate the middle section from the rear section.

[jlevie]

You will probably have to remove the entire drive shaft to get the halves separated and the splines cleaned and re-lubricated. You will also need the drive shaft out to assess the condition of the u-joints.

In almost all cases a failure of the rubber mount of the CSB will be the result of binding u-joints in the drive shaft. While you can gain temporary relief by just replacing the CSB, the new part will have a short life. The only long term fix is replacement of the drive shaft and CSB. Most rebuilt drive shafts will come with a new CSB installed.

[capitoljake13]

Just to follow-up.. I ended up swapping the pipe wrench for a pair of channellocks and was able to properly loosen the collar nut. (I only dropped the exhaust and never fully removed it from the headers so I had a little less space to work with)

Just kept turning until it was completely removed from the threads. Then a foot on the rear tire for leverage and a hard yank and the mid section came out of the rear. Swapped the Center Bearing, cleaned out and greased up the splines, bolted on the new guibo and put it back in.

I never fully removed the rear as I only wanted to install the parts I already had. Will just have to keep an eye on it and if it starts tearing the new center bearing I'll work on swapping the driveshaft all together. If it comes to that, at least I'll get a chance to put in the new rear transmission seal that I purchased last week, and found sitting in the bag after everything was buttoned back up.