Seeking front diff wisdom (2 Viewers)

[Freeborn]

Hey, team. I have a '02 with the "clunk" that happens shifting from reverse into drive (and often when downshifting to climb). I've isolated the problem to a bunch of play in the driver side of the front diff. Like if I'm under the truck, I can put my hands on the front drive shaft and the driver CV axle and turn the drive shaft 1/8 (or more?) turn before the CV axle starts to move. The passenger side CV engages almost immediately. The CV axles are both pretty fresh.

My question is this:
Has anyone here ever dealt with something similar? Is there a way to figure out definitively if the problem is the intermediate shaft coming out of the diff or if it's in the diff itself without disassembling the whole thing? Has anybody here ever replaced that intermediate shaft?

What I'm trying to avoid:
If the problem is just that I need to replace the intermediate shaft for a couple hundred bucks, that would be awesome. If I do that and it turns out that I need to replace* the diff itself then I've just cost myself a bunch of time and money unnecessarily.

*I say "replace" because it's relatively cheap compared to a rebuild.

 

[excessive]

could be just a worn drive flange, always check the cheapest / easiest thing first

 

[TahoeZ]

The front diff is open so engaging at different times is normal and does not indicate an issue. I did have a slight clunk out of my front diff at 250k because of wear but most of my clunk was front diff bushings and CV/hub flange splines.

 

[Freeborn]

Right...
The flanges are also new. So are the bushings.

The play is pronounced on the driver side at the tripod end of the CV. Like the CV doesn't move at all on the driver side for a while when turning the drive shaft and is distinctly different from the passenger side. It's way beyond what I've seen as normal slack in a diff. And the clunk is violent. I'll see if I can post a video that captures what I'm seeing...

 

[Freeborn]

Here...

 

[Freeborn]

Giving this a bump to see if anyone has any thoughts...

 

[Malleus]

Bushings

 

[Freeborn]

I genuinely wish it was bushings. To add another piece to the puzzle:

When I back out of the driveway, I can avoid the clunk when I shift into drive by pausing a moment in neutral and turning the wheel in one direction before shifting into drive. When I do that it's smooth.

To me this reinforces the idea that it's in the diff itself, but I'm wide open to cheaper/easier ideas.

 

[Malleus]

I was genuinely surprised how much difference differential bushings made when I replaced my son's 25 year old rubber. The differential design relies heavily on those bushing for support. Crawl under the front end and look at it. The only supporting connection the differential has to the truck are those three bushings.

If you're already replacing the CV axles, the front and rear bushings are easy to access. As @flintknapper has posted here (Post #75), cutting the old center bushings out with a hole saw significntly reduces the removal time. Installation of all three is easier than removal.

 

[Jack90210]

The flanges are also new. So are the bushings.

To be clear, ha.

 

[M0N0LITH]

The intermediate/extension shaft in the diff may have worn splines. It could also be the inner joint splines (if your CVs are old). The clunk is often an issue of tolerance stacking from multiple components so it can be difficult to isolate it to one component.

 

[TahoeZ]

You said the flanges are new, but what about the axles? Worn splines on the CV axles is more likely. If you’ve already replaced axles flanges and bushings then sounds like the diff is the most likely cause.