Clonkity-clonk 8.25

'93 XJ, 4.0 HO, 2WD, 8.25" rearend.

I'm trying to track down the source(s) of some annoying clonk noises
coming from the 8.25" rearend on my Cherokee whenever I lift up off
of the gas pedal.

With the parking brake set and tranny in "N" - the drive shaft
can be rotated freely (by hand) about a 3/8" before the gears
engage and stop the driveshaft.

I'm guessing that the side gear thrust washers are worn.

I know that you're supposed to check the side gear clearance
with a pair of feeler guages - but doesn't the ring gear prevent
checking the side gear on the left side?

...also...

I noticed today that when the rearend is jacked up (parking brake off),
I can grasp the tire (both sides) and slide the axle (again, both sides)
in & out of the housing by about 3/16" - 1/4" (accompanied by a definite
clonk sound).

What's going on with this?

Last time I checked (8 months ago) the ringrear & pinion backlash
was OK, and the C-clips looked fine and appeared hardly worn.

Is the there a spec for the C-clip thickness that I can check
with my mic?

I know that the C-clips prevent the axle(s) from coming out
of the axle housing - but what is there to prevent the axles
from sliding inwards too far?

Is there something that I'm over-looking?

Thanks, all.

There are shims of varying thickness available or place under the side gears.C-cilps only come in one thickness and the cross pin keeps the axles from going in too far.
I had the same problem with a high milage 8.25,replaced it with a D44.
Looking in the FSM,a solution is either replace the side gears,case or both.
Wayne