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BLKWDW
16th March 2013, 08:53 PM
Hey all my brothers shorty mav has had a clunking noise coming from the front diff for a while now. It only happens in 4wd and when turning and is most noticeable when hard lock turning. If you unlock a hub it goes away doesnt matter which hub but once locked in its back. Driving straight it doesnt mmake the noise at all.

At first i thought it might be a dodgy manual locking hub but i put mine on his and still the same.
I next turned to the cvs. we pulled them out today and both seem to be fine. no cracks or damage noticeable. So we pulled the diff out. It looks fine. By the noise it makes if it was the diff i expected to see some grinding marks on the teeth. I was hoping it would be the spider gears as i have a spare set but from an appearance perspective they look fine. No marks on the crown wheel or pinion i could see either.

The oil did look very old as well so was long overdue for a change.

So my question is what could be the problem?

BLKWDW
17th March 2013, 11:13 AM
Anyone!!!!!

BLKWDW
17th March 2013, 11:29 AM
I should actually mention that when removing the cv we noticed that the passenger side swivel hub is leaking and in both swivel hubs the grease was runny especially the passeneger side where the grease would drip of my fingers like water.

Bloodyaussie
17th March 2013, 11:53 AM
Well with out pulling it apart you are only guessing but CV's??

The seals obviously need replacing.. how long have they been leaking, when was the last time the oil was changed, how much oil is in them....

The seals keep the oil in the diff and the crap out.. if they are stuffed then the gears are not being lubricated properly and heat build up and foreign crap out!!!!

I am not a diff expert but have rebuilt my hubs a number of times and have had damaged CV's in my old Hilux.

MudRunnerTD
17th March 2013, 12:51 PM
CV for sure mate. The contaminated grease is a result in the inner axle seal leaking the diff oil into the swivel hub as BA mentioned.

With the CV out of the car and cleaned of grease how does it feel? Move it around it full motion, any tight sections, before a CV explodes it tends to either chip around the center of each ball or swells up a little and tightens up. It can look clean and I. Good Nic. If its clicking its knackered mate.

nissannewby
17th March 2013, 12:51 PM
Sounds like a cv. The front diff is open and with one hub locked the drive will always go the easiest option which will be the unlocked hub everytime and being there is no load on it there will be no sound. Hope this makes sense.

Get a second person and put it 4wd and do some circles see if they can pick which side it's coming from.

BLKWDW
22nd March 2013, 04:43 AM
Well my brother took the cv's to the mechanic yesterday and he said both of them are in good nick. He thinks it may b the wheel bearings but im not so sure. Think we'll put it back together with the new bearings we already had and see if it does it. If ut still does we'll just keep driving it till sumfin lets go. If its a cv then we hav a spare new one.