96 bravada front end clunk clunk clunk on accellaration.

[timisback4584]

I have a 96 bravada with smart track awd. whenever i accellerate all i hear is clunk clunk clunk coming from the front end. Someone told me that it's the transfer case. they said the chain is probably loose and jumping teeth. is this a likely cause for the sound? Can i determine if the chain is loose without dropping the transfer case? if the chain is loose does the whole thing need rebuilt or can i just replace the chain? is it complicated? sorry for so many questions. thanks, Tim

[Chris Stewart]

I'd try setting the parking brake with the engine off, transmission in Park, jacking up the drivers side front wheel a few inches, properly set a jack/vehicle stand in case the jack fails then..

turn the tire clockwise & counter-clockwise and look for excessive rotation in the constant velocity joints(both sides) and front differential shaft.
If the joints look like there's no excessive play/slack but the front driveshaft is turning 1/4 turn at the front of the transfercase then excessive transfercase chain/sprocket/bearing wear is suspect.

All help gratefully accepted.