Drivingthe 4runner back from a round the town trip with the kids. I turned into my neighborhood and noticed a loud squeaking as I drove. I didnt notice it at all during the day but just seemed to come up. I get home and jack the front up and spin front wheels. No noises. Jack the rear up and turn the wheels and I get no noises from the wheels. I put the rear axle on jackstands and start the truck up and listen. I hear a squeaking. I turn the truck off and grab the driveshaft and notice i have about a inch of play when i turn it before it starts to turn the pinion. And there is a squeaking resonating through the driveshaft when i turn it. So I have two places to look. Tcase and the 3rd member. I recently reinstalled the 3rd member after putting in an open carrier to repalce the welded one. I reset the backlash to spec and put it back in. I am thinknig somehow the adjuster rings released or slipped and the backspacing is way out of spec. I did tap on the bearing caps to make sure everything was seated and made my spanner wrench to tighten it down. I am placing bets there. BUT I do know the front output shaft bearing is growling pretty bad when you turn the front driveshaft by hand. Not sure about the rear output, but i plan on rebuilding the Tcase eventually. Right now I am trying to gauge what damage I am doing to the rear gears. Has anyone else expereicnes this squeak throguh the driveshaft? Ujonits are in great shape and I do not think they are a contributer to the noise.

 

well...i had almost the same exact problem. loud squeeks mainly when i would let off the gas and it was still in gear. it was a bad bearing on the output shaft. i let it ride for a while unnoticed. i went wheelin and the slop the stress from 4 low put too much stress on it and toasted the gear. also. the u joints may look fine now...but let it ride much longer and they will need replaced too.

 

U joints have made squeaking noises for me before.