Well, I have a 98 Tracker, 2 door, 185000 miles, 5 spd, 2" calmini lift (since 50,000 miles) and 235 x 15's on 7" wheels (all since 50,000 miles).

A few weeks ago, had the right (passenger) side axle pop out of the differential while climbing my way through a modest sized rock pile.  Got home, tested it straight on to a dirt face.  All seemed well (tires slipping).  Ran in circles, got the axle to do it again when turning right.  Figured out what was happening (the axle was very slightly extended from the drifferential when at rest).

Pulled the axle, determined the likely problem, as the last 1/4 ~ 1/2" of splines were wiped off and smooth.

Took a GV front diff and a (supposed) 5:12 Trackick diff to get it set up (been saving them for this at least 3 years), as I figured the right side gear was likely damaged (and certainly wasn't going to be clean, with all those spline bits in there).  Ended up the aluminum unit had 4.62 (or so) gears in ot, so I took my origianl front diff to the shop for the gears.

Installed it, along with an axle from the junkyard (well, the inner cv, the junkyard one's boots were starting to crack).  Then tested it.  Same thing.

Took it back to the shop, who wanted to see it all installed.  They suggested that I should replace the inner snap ring every time an axle is replaced.  I let them do it, as I had no time.  They tested it similarly, in circles, dirt and asphalt.  All was supposedly well.

Finally had time to test it.  At zero degrees and snowing.  Two things:  Now I have significant gear whine with just the hubs locked (should I expect this to 'break in'?), and the darn thing is popping out while going straight (in 4wd) -- though not fast like before (not quite what I call an improvement).  I am going to call them tomorrow.  Wondering if anyone else is familiar with this problem (popping out axles).

Thanks!

I had a similar problem when I had 'a little extra wheel travel' out of my calmini 3" kit (from improper instalation). More often the inner CV would pull past the retainer clip in the cup. But after replacing one of those issues, mine was poping out like yours.... due to the inner snap ring 1- not being replaced, then 2- being improperly installed, 3- not being properly installed again  then I got it right... and it was back to the CV pulling out of the inner cup. After that I started bugging Calmini and realized what I did wrong (did not flip my upper strut mount back to norm when installing the spacer that comes with the 3" kit).

Your axle should be difficult to pop in and then need something prying on it for it to come back out.... Is it a tight fit? If you can remove it by hand, something's not right.

Zig

I've been looking on line and can't find any particular listing for the circlips.  Going to call around locally.  Also going to see if I can find out if the inner cv joint is different for the GV diff (don't see it being so, but worth finding out).

Might luck out!

I think the snap rings come in the boot kit - at least I got them when I bought an SGP boot kit for my 2.0 Grand Vitara.

Well, took the inner cv apart, decided to try the cage assembly installed in reveres (maybe more angle).  Opened the retaining spring up a bit, no change.  Still pops out in 4wd.

Arrggh!

Not apparent movement laterally in anything (even took the strut off of the hub/carrier assembly).  The strut seems good (OME) and no feeling the upper mount is loose (worn out).

Really starting to feel dumb here.  Can only think that MAYBE the whole gear cluster got moved to the GV carrier -- bad side gear???  Reaching here, I know.

Alright, back to the top.

Updates:
Shop couldn't figure out what is happening and almost subtley point at the lift kit (after 130,000 miles).  There only suggestion is new side gears.  Which is not unreasonable, but another $700 is just a bit more than my wallet wants to do.

So, off to the junk yard I bought a front diff out of a clean very stock 4 door.  Problem is that diff assembly has the same issue:

As you go forward (straight line) the truck steers right until the stress releases (along with a large 'clunk' -- not unlike a very large cv joint, but much slower) and the pressure on the steering releases.  Followed by a modest build up until it does it again.  A bit unnerving on snow and ice packed roads.

In a sharp turn on the pad in from of my shop (to the right) it pops regularly, seeming to come from the diff.  I don't see the 1/2 shaft popping out of the diff (from 10-20' away anyhow).  I put it on 4 jack stands and ran it in 4x4 and had my wife steer it both ways to watch for any strange behavior -- not stress on the front, so only limited data.

I am trying to think out of the box and think of a contributing factor, like ring & pinion putting certain stresses out (ie, in 2x4 on soft ground one rear tire tends to get more torque on it and spin).  Or I had a bad cardin (double u joint CV) on an F350 that went bad.  Seemed like the noise and problem only happened when the right front hub was locked -- it turned the drive shaft more than the left front, which then made vibrations.

Maybe I can raise the rear tires in the air and drive it on the front axle only (in low range) and see what's going on. 

Anybody in Denver/Colorado Springs area curious to try out the GV diff assy?  I need a sanity test!

Are you absolutley sure the gear ratios are the same front and rear?

Are you running same size tires/wheels on the front?  Not using the spare?  That clunking almost sounds like a locker unloading. 

I pulled the diff out of a 97 (or 98) manual trans truck.  Low option model.  But, the same results as the other two diffs. 

Same tires/rims (not moved).  I even swapped the hubs left<>right.  Didn't expect any differences, but only took 5 minutes.

Keep teh ideas coming, as I am fresh out!

I know this a long shot, but is it possible for you to post up some good pics of you front end lift and diff setup?

Well, took the inner cv apart, decided to try the cage assembly installed in reveres (maybe more angle).  Opened the retaining spring up a bit, no change.  Still pops out in 4wd.

Arrggh!

Not apparent movement laterally in anything (even took the strut off of the hub/carrier assembly).  The strut seems good (OME) and no feeling the upper mount is loose (worn out).

Really starting to feel dumb here.  Can only think that MAYBE the whole gear cluster got moved to the GV carrier -- bad side gear???  Reaching here, I know.

Did you inspect the outer CV?  I know they don't (at least to me) seem to break often as the inner's, but we are running on long shots now.

You should check the ratio of the rear diff. It's a 98 5spd so should have been 5.12 stock but you also said "Ended up the aluminum unit had 4.62 (or so) gears". Perhaps some PO put in taller diffs?

I'm also wondering if perhaps you have a bad A-arm bushing. would explain "clunking" and could provide just enough extra movement to possibly dislodge the inner cv stub.

I guess I have confused the issue:  the original gearing is 5.12 (still is).  The two diffs I had on hand were meant to be combined at some date into one; the aluminum unit was supposed to be 5.12, but was a 4.62:1 r&p.

Hence the original diff r&p had to be used when I used the iron 3rd member. I had hoped that the tech doing the work also did not use the original side gears, but he did.  So not as thorough a change as I had hoped (always a question when some old parts are being used as well).

I replaced the a arm bushings a year or so ago when I was freshening up the steering (which is still sloppy -- one more part to find -- the center link).  The old bushing was fine, but cheap enough set of bushings from calmini, and I wanted to have thoroughly gone through the basics on it.

More ideas please!

When you pull the CV shaft out of the diff, look in there with a flash light and see if your side gear is messed up.

I did take a cv stub and inserted it in both the steel diff (old r & p and side gears) and then into the Vitara/GV gears.  Much harder to pull out of the Vit/GV gears. 

Anyone have any instructions on taking off the side gears and replacing them?  I figure the Vit/GV side gears can be swapped in.  Looks to me like they are retained with a screw in retainer that uses large pin spanners.