What would cause a clunking noise when you take your foot off the gas pedal fast but not when you take it off slow or push in the clutch This is happening on your 1979 CJ7 with a 3-speed manual?

Answer 1

two things mainly either your motor mounts on the engine or what i think the transmission has what is called a cross member that basically bolts the transmission to the frame of the Jeep it is hard to miss to check the motor mounts simply put a jack under the engine at the oil pan (place somethin between the oil pan and the jack to prevent a chance of puncture) then jack the engine up a very little bit and look at the two motor mounts they are on either side under the exhaust manifolds also check the bellhousing on the transmission (where the tranny bolt to the engine) make sure they are tight. i know this one... i have the same prob on my 240sx. its the body mounts that hold the susp. to the body. in the rear. like when you are in reverse put the clutch in and then hear a clunk, same thing if you are going down the road and let off the gas suddenly then it clunks. Might also be a driveshaft U-Joint about to go.