hammer on the frame!!! ahhhh

[nhfj40]

I have 73 fj 40 that had a loud snapping noise comeing from the transfer case area like someone was hitting the frame with a hammer!!. in inspecting it it looked like i needed to pull and rebuild the tcase for a number of reasons play in the front output shaft, oil leaking all the time out of it and way to much play in the drive shafts . instead of useing the old 4 speed case I rebuilt a 3 speed transfer case and pulled my old 4 speed t case out and in pulling it I found the 4 speed transmision output shaft t be badly worn in the area were the t-case drive gear is. almost an 1/8 of an inch of play on the shaft so I bought a rebuilt four speed with the lower 1st gear from SOR and installed everything It drives great ! really smooth and great slow low range, highly recommend it if you want to crawl with. The 3 speed case and the low 4 speed transmision were meant for each other!!. But the noise is still there not nearly as loud or as frequent. I am running 35x12.5 tires it has a lock right locker in the rear and I had a 4 wheel drive shop put in put in a new ring and pinion last summer. any Ideas! is the locker causeing it to make that noise?? I am also running a stock 2F motor if that makes any defference.

 

[HI^C]

locker
spring bushing
ujoint
shock or shock bushing

I assume spring over, do you have a traction bar?

 

[nhfj40]

no it does not have spriing over. it has new U joints as of last summer, would they go bad that quick? I have a 4' lift with greasable shackles and new BDS shocks all around. I think it has something to do with the drive terrain it doesn't do the noise unless I am moving , meaning I can't re create it by jumping up and down on the bumper.

 

[Romer]

Is the skid plate loose or does it have any snapped bolts?

 

[Mace]

Lockright in the rear?

More likely than not it is a locker issue.

 

[e rock]

Are you sure it's not coming from the lockright? Under what driving conditions do you hear the noise?

If you don't know what your locker sounds like, stick your head out the window as you slowly coast in circles in a parking lot. You'll hear (and probably feel) it ratcheting to differentiate. If that's the noise you're noticing, it's par for the course.

Eric

 

[nhfj40]

I know the noise the lockright makes from turning on pavment, the noise seems to happen on down hills when the right rear tire moves up a little and I mean a little like 3" or so. I have moved the shocks in clsoer together on the top rear cross member so the rear wheels could articulate more. but I can't see how that would make a difference, I don't have to do anything extreme to make the noise happen. and its not the skid plate because that is off right now.

are lockrights just junk? does a lockright make the rear end a little looser than normal?

should I move the shocks back to the stock location?

 

[Romer]

Did you recheck the toque of the shackles. The brackets that hold your springs to the axle should be torqued to 80 lbs. These ALLWAYS loosen up after installation and should be re-torqued after about 500 miles. Don't know if thats your problem, but something worth checking.

 

[hammerhead]

are lockrights just junk?

LRs kick butt. They click, they pop, they occasionally even bang. They are NOT, however, junk. Oh wait, yes they are. You better pull that out of there before you drive it again and put it in a box. Ship it to me for evaluation. Yeah, that's it, evaluation, hehe.

 

[nhfj40]

I plan to check it out next week I'm not sure if its the LR or play in the ring and pinion, I'll keep ya posted.