tranny or rear end knocks when you get on the gas.....

[davetheman81]

ive noticed that either when you have shifted ( any speed ) when you get back on the gas even lightly there is a knock that sounds like its coming from the middle to front of the car, if you relase the gas going about 30 and lightly hit it , you will here the noise, im new to all wheel drive, maybe bad center diff? could it be the input shaft ? it sounds like something is loose and when you let of the gas it gets loose, so when you get back on it, it has to catch, and thats the knocking noise, any suggestions would be great, i may be able to put the car on a lift to tonight so what should i look for? thanks

 

[derektcasey]

That would be Drive-shaft thump. Your carrier bearing are probably shot. Not too har to fix. You can rebuilt the entire driveshaft (new U-joints and carrier bearings) and re-pack the lobro-joint for just under $200 would take about a day to do.

Some like to try the Thump-Fix using roofing/flashing silicon to fill the carrier's. But, this takes longer. Plus you take a chance at causing a constant vibration (I know form experience) if they get a little off-center while curing.

VFAQ.com has a write-up on both the rebuild and the thump-fix.

 

[davetheman81]

thanks casey is there anything in particular i should look at when i have her on the lift?

 

[derektcasey]

Grab ahold of each section of the driveshaft and try to move it up and down. If it is bad, you will see lots of movement (and cracks in the boots) of the carrier bearings. Seeing that your car is a '90, they are probably worn-out.