"Clunk Noise" from drivetrain

[hntashdjian]

Hey everyone,

I test drove a stock 94 today. Everything seemed to be ok until i put the car in reverse and heard a loud "clunk" noise. Everything else was very smooth. Once i accelerated from a stop, i heard the clunk again. Also, if you let for of the gas while going around 5 mph and give it gas, you hear the noise again.

On my old 94, there is a screw that adjusts the idle(correct me if im wrong). You cannot see the screw unless you open the top part(drill through top hole). I think its part of the air sensor unit. On this car, it was opened and the screw is visible. What does this mean ? Ive seen many 80s with that covered.

Thanks in advance,



Harry

 

[Vitesse_6]

Could be the drive lines needing grease, Does it have rear disc brakes?
Mine clunks for a number of reasons.
Its a start.
Good luck

 

[Cañonero]

I have a similar problem.

When I'm stopped with the brake pressed and I change from reverse to D and from D to reverse, I hear the clunk. The same if I quickly press the accelerator. It looks like there is something loose down there. I think it could be a driveshaft, axle shaft or a birfield.

Most of the diesel 80 with manual transmission and powered engine have some kind of looseness down there because of the big torque of the engine and because they don't have a torque converter that smoothes the sudden power transfer.

What worries me is mine (and yours) are automatic. My engine is powered as well, so, what REALLY worries me is thinking about the chance that the looseness is in the transmission or in the torque converter.

If the problem comes from the shafts, I wouln't worry much, I know people that have run with them this way for years without problems.

I'll tell you when I find out where my clank is, so it can help you to locate yours.

 

[Squash]

Grease the d/s to begin with, whlie you are down there check the "U-joints".

I like standing the truck on jacks, this allows you to turn the drive train with your foot by kicking a wheel. A tight drive shaft will have no play between u-joints.

 

[sicksixty]

I too suffer from this clunk in the drivetrain. When the truck is in park I can stand on the rear wheel and rock the truck foward and reverse at least an 1 1/2 inches. Awefull lot of slack in the drivetrain. Surely that is not a lack of grease. Anyway, mine is a 92 FJ80 and I am going to be setting her up on 33" with an OME J lift kit in the next couple of weeks. Parts are on the way. I plan on doing investigative work then. I will let you guys know what I find. In the mean time, I would love some suggestions of things to check, lube, etc while I'm in the break down and build back up stage. Example: I'm thinking of investing in a FZJ80 rear axel to gain full float and rear disc. Let me know what you think.

 

[jonheld]

Guys,

There is a lot of slack in a 4WD drivetrain. You're driving a 6000 pound truck with 1 ton running gear. It's gonna make some noise. Simply count up the number of interfaces in the driveline.

FWIW mine has been clunking for the last 190K miles. Keeping the driveshafts properly lubed will help, but it will always have some clunk.