Thumping sound coming from driveline.

[duece21]

For about a year I have been swapping from my swampers and BFG AT's because i picked up the TSl's for cheap. Recently I went back to the BFG's for the snow and I started hearing a thumping sound that was timed with the driveline speed. First think I thought was a U-joint, but both are tight. I lifted each tire and spun them around and found no flat spots or bad rotation. The right front caliper is catching a little bit and probably needs replaced, but when i got to the rear tires I narrowed the sound down to the transfer case and tranny. Question is what causes that, bearing or gear catching on something? 700r4 and 208 combo. Thanks in advance.
Jesse

 

[K5Jimmy]

I'm working thru the same sorta problem now, except that mine is not timed with driveline speed....sorta erratic.

I felt mine while holding the shift lever, and was able to affect it by moving the lever a bit, or shifting to 4wd.

I bought the bearing/seal kit ($122) and dismantled the TC...there I found the range fork was ground down to a knife edge, and couldn't hold the teflon pads....so I ordered that ($52), and a new chain ($92) just because I have it all tore down

It's all snap rings...I've got about 3 hours invested in it so far replacing bearings, seals, etc....and I've cleaned Everything really well...took about 20 minutes to drop out....there are 2 snap rings that are real boogers, so make sure you have quality snap ring pliers

Wrecking yard wanted $250-$400 for used...rebuilt runs in the $600-$800 neighborhood....I will have $250 in mine, plus I now know what's in it...

you'll also be doin yourself a favor to have seal puller for one of the bearings, and a couple of the seals

 

[duece21]

Yeah its definitely transfer case, I put it in 4wheel this morning and heard a terrible noise, sounded like maybe chain going out, but who knows, I'm going to check pull & save next week for used if not its time to start pullin it down.