Thread: Clunking Gears

mmmm is your centre diff lock engaged it sounds like transmission wind up

has the car been driven for some time on bitumen with the centre diff locked engaged

Im thinking center diff or Uj's on the box side of the shaft..

But play it safe since you have an auto cog box drain the oil and inspect it, remove the pan/filter and inspect that...

Inline with my rant posting elsewhere, Autos are critical on oil the slighest problem in an auto WILL show up in the oil and filter first giving you plenty of notice of what the problem your about to have is.

Replacing the oil in an auto is like having a quiet beer after a bad days work, It wont make the problem go away but it will let you get through the next day.

Transmission wind up is an interesting one. I have never used the centre diff lock on tar and tend to only use it when required.

Is there a check for centre diff lock function? Is it possible that even though the warning light operates that the centre diff lock remains on ?

U/j’s is a possible although all have been replaced recently but not saying they haven’t failed again. I shall check.

Originally Posted by Mangie

Is there a check for centre diff lock function? Is it possible that even though the warning light operates that the centre diff lock remains on ?

Sure is, put the park brake on, put it in gear (park for autos), check that the CDL is in the off position, jack up one front wheel and try to turn it. It should turn and be fairly quiet about it.

Next put the CDL on and then try the wheel again it should turn a bit and come to a sudden stop with a clunk as all the drive line gears take up slack. Turn It back the otherway and it should turn less than 1/5th of a turn(ballpark) and come to a sudden stop with a clunk.

Any thing different and its time to fault find the drive line from the tcase forwards.

One wheel off the ground with the difflock apparently off and the wheel won't turn. Major problems do you think ?

Originally Posted by Mangie

One wheel off the ground with the difflock apparently off and the wheel won't turn. Major problems do you think ?

Yep not good

I had a jaguar that did the same - sounded like the rear diff was playing up - just turned out to be low oil in the auto transmission and the vibrations just sounded as if it was coming from the rear. The pump in the gearbox was losing oil because of the low level in some situations.

Easy to double check - failing that check the diff lock as others have suggested.

Gazzz

no motion of the front wheel when up and CDL apparently off is no good the CDL is stuck on for one of a few reasons.

1. the selector is damaged and stuck on just enough, which is usually the first part that leads to one of the 2 following.
2. The lock mechanism is stuck on its splines
3. the gears in the CDL are FUBAR.

items 1. and 2. can be field repaired fiarly cheaply if it hasnt been stuck for too long item 3 not so... in any case 2+3 require you pull the center diff case off the tcase to effect repair. Item 1, if youre lucky might just be fixable without too much cost or effort.

Keep the front wheel off the ground, and have someone rock it gently back and forth against the driveline while you apply love with a small hammer, shifter or prybar to the control linkage of the cdl, If you have the vacume operated one pull the diaphragm thingy and operate the linkage by hand

Copious quantities of wd40 are the go and it will help if you drain the tcase and fill it with 5wt engine oil while you do this. DOnt drive it with the 5wt in it.


Good luck with it