Axle troubles

[swalve]

While I was changing a motor mount yesterday, I noticed that my axles were loose in their holes in the transmission. It's a 97 Grand Prix GTP (so it has the 4t65e-hd transmission).

(Apologies for not using the technical terms- I forget the names.)

I'm pretty sure they are the original cv shafts. By loose, I mean that I can easily wiggle the inner "cup on a shaft" thing- the piece that goes into the transmission and that the mid-shaft of the cv axle goes into. Probably a few degrees of play off of center.

Weird thing is that it's not leaking to any appreciable degree- a half a pint a year maybe?

My questions are, and I know this is mostly trying to read tea leaves:

1- I looked at some online diagrams of the transmission, and wasn't really able to tell- is there a bearing inside the trans that keeps the driveshaft in place? Or does it just "hang off" of the output shaft?

2- Do you think this is just worn splines on the driveshaft? Or could this be loose/worn parts in the output/differential part of the trans? I would hope that the parts in the transmission would be "harder" than the driveshaft, so that if wear was going to occur, it would be in the driveshaft and not the transmission. But who knows?

3- Any recommendations on good/economical brands of reman or new driveshafts?

I guess what I'll have to do is just get new driveshafts and see how they are once installed. It's an old car, but I really like it and want to keep as long as possible.

Thanks in advance!

PS- Wow, what a difference new mounts made- the right hand mount was completely collapsed and the engine was just sitting, metal to metal, on the frame. It happened gradually, so I didn't really notice that they were bad until they were really bad. I expect that this misalignment probably caused some of this problem. I used the cheap Anchor mounts, but I did get their hydraulic ones. They seem to be better than the usual garbage that Anchor has. We'll see how long they last...

 

[eljefino]

I need pictures of this "cup on a shaft" you describe. There will be slop in places in the CV system but I agree angular deflection from the differential sounds odd. Still I wouldn't worry.

 

[Kestas]

Our company makes seals for many GM transmissions. Though I'm not familiar with your application, I know some of these seals are specially made with bellows (or more exactly, a "bellow", if there is such a word) to compensate for movement of the axle relative to the housing, while at the same time maintaining a tight seal.

 

[punisher]

Its normal. Inner CVs have a bit of "slop"/wiggle room where they go into the transaxle. I have never worried about it unless I had an inner CV vibration problem that damaged the bushing.

 

[swalve]

Originally Posted By: eljefino
I need pictures of this "cup on a shaft" you describe. There will be slop in places in the CV system but I agree angular deflection from the differential sounds odd. Still I wouldn't worry.


Diagram In this diagram, it's labeled inboard CV joint.

Originally Posted By: Kestas
Our company makes seals for many GM transmissions. Though I'm not familiar with your application, I know some of these seals are specially made with bellows (or more exactly, a "bellow", if there is such a word) to compensate for movement of the axle relative to the housing, while at the same time maintaining a tight seal.


Excellent! That would explain the no oil loss.

Originally Posted By: punisher
Its normal. Inner CVs have a bit of "slop"/wiggle room where they go into the transaxle. I have never worried about it unless I had an inner CV vibration problem that damaged the bushing.


Yeah, there is a little slop that doesn't concern me. Just starting to ever so slightly clunk when going from D to R.

Thanks for the replies guys, really appreciate it. It sounds like I'm probably just at the wear limit.

Keep 'em coming, if anyone has anything else to add.

 

[mechtech2]

Could be splines that are a bit worn, or the bearings.
This mild leak condition may not get worse, at least for a LONG time.
But keep an eye on it and keep your fluid from getting too low.

 

[swalve]

Quick update: I replaced the driver side axle over the weekend, and found that the output shaft in the transmission was pretty loose. There was some end-play, and a lot of side-to-side play. The good news is that there was no slop in the differential itself, and the splines were not worn. But it seems like there should be a bearing in there somewhere... What keeps that end of the shaft and the inner cv joint centered?

Any thoughts?

As for the axle, it was worn out. I got a new one from Autozone and it seemed like a quality unit. Oddly, this part was listed as "new" and $60. Their reman part was much more. Will be doing the other side when time allows.

Also, there was evidence of fluid leakage, but it was obviously a very slow leak. The mating surface of the axle that rides in the seal was slightly worn, so I would expect that the new axle will probably stop it from leaking at all.

 

[mechtech2]

The carrier bearings.

 

[Kestas]

mechtech2 is correct. Differential carrier bearings are designed to be under preload. There should be no slop. When slop is present, it not only is bad for the bearing, but it also can prematurely wear the seal when rotating off center.

 

[swalve]

Will investigate. Thank you!