kissthis66

When I am sitting at an idle, clutch not pressed in, not in gear or anything I can hear a raddle/banging/clunking noise coming from what seems to be coming from the tranny possibly motor but Im unsure. The motor idle fines, no misses or anything so I really dont think its that. Also when im driving in 5th gear and release the gas to coast, i get a really bad vibration coming from the drive shaft. It only does this vibration when in 5th gear and release the gas while its still in gear.

I first replaced the rear u joints and removed the front drive shaft(just eliminating it from the equation until this issue is resolved). Didnt fix the problem.

Thought it could then be the transfer case, as the rear output shaft had what seem to be a lot of play. So I swapped it out with another good one and it didnt fix the problem.

I then jacked up the rear end and tested to see if the drive shaft was bent by putting it in 5th gear and letting it run. The shaft didnt seem to vibrate at all. Basically it had little or no play. I did notice that where the rear drive shaft hooks up to the rear end had what seemed to be some play as it was running. but this could be normal, im unsure.

I then went on to replacing the clutch because it was about due and thought it could be the cause. During the installation I found that the top tranny bolts were gone!!! And the ones to the upper right and left were lose enough to be removed by hand. I swapped out the clutch, tightened the tranny back in there and still have the issue of the noisy idle and vibration while in 5th gear.

So at this point I dont know where to head. Im not sure if the tranny has gone bad due to the bolts coming off and the weight and angle of the shaft messing something up inside or what. I guess my next action would be to replace the tranny, but im dreading dropping a $100 bucks on one to find out mine was fine to begin with.

Any advice on where I should continue my look? Please help as this is my daily driver. Thanks everyone for at least taking the time to read this!

s14unimog

I can say that the trans is definitely taking the most bearing loading in 5th gear. How many miles are on that transmission? I would have suggested the transfer case originally but you seem to have tried that. Fortunately I doubt the missing bolts allowed for much movement/separation of the transmission so I'm doubtful that's related. You could try rebuilding it. I rebuilt my AX-15 when I had a 3rd gear grinding issue. turned out that it was a worn shift forth but before noticing that I just replaced all the blocking rings and bearings. Although it wasn't the problem, my driveline is sooo smooth now. I had about 140k on my trans.

kissthis66

its a 94 and has 180K plus the miles that haven't been logged due to the missing TC gear...so my guess is probably 200K +/- miles on it. I doubt its ever been rebuilt.

jeremy175

Did you replace the pilot bearing when you replaced the clutch?

kissthis66

Yes, I bought a clutch kit from Autozone and rented there $160 tool to remove it. (the free loan a tool program)

s14unimog

I'm betting its a main shaft bearing in trans. It's practically all that it could be.

kissthis66

Kind of thinking the same thing. Was going to head down to the junk yard tonight and grab me another tranny as they are only $100 bucks. This way it gives me another one to rebuild.

Thanks for the input and help guys, hoping this $100 isn't wasted on a part that didn't need replacing. Oh the joys of owning rigs other abused before you =)

s14unimog

^wow you're lucky if you can find one. I have never even run across a manual one in the junk yard but then again the yards around here are lacking on selection.

kissthis66

well i will find out tonight/tomorrow if they have one or not. luckily i have like 4 different pick-n-pull yards to pick from here in Sacramento...so crossing the fingers one is still around.