CLUNK and loss of front drive

[NeedMoreBoost]

Hey all,

Have discovered this issue. The vehicle has made the CLUNK a few times previously but never loss of 4wd.

Hi or Low 4, doesn't matter. Under load e.g. up a steep hill, down a steep hill or giving it berries in mud. Will be driving along, hear quite a loud CLUNK and the front end will lose all drive. Taking the load off brings 4wd back until too much load is applied and it happens again.

The vehicle is a 1997 D22 with a QD32.

I am thinking a few possibilities:

Hubs - One or both slipping out of engagement. Being open diff, one slipping would cause only that side half shaft to spin hence no front drive. Both feel like they are engaging and the teeth look pretty good from a quick inspection.

CV - Same deal. Left hand side is new, heard the noise before its replacement so not that one. I would expect more CV type noise as well but it is a possibility?

Diff - Something in there is cactus. Would more likely be constant noise though and not able to lose and regain 4wd?

Transfer chain - I would not expect it to make only a clunk, if it were slipping I would know about it!!

Front drive shaft - maybe some splined surface is worn, if they have one? CVs check out a-ok.

Only other drivetrain issue I currently have is a cactus drivers engine mount, perhaps extra movement of the engine is causing something to slip out of engagement somewhere? Seems unlikely to me however.

What do you blokes think and are there any other possibilities? How do I check suspected components properly?

Cheers all,

Andy

 

[happy john]

I would say one of the hubs is slipping out of engagement under load,i have hade the exact same issue on the left side. Rather than stuff around as it was worn I replaced mine with aftermarket ones. You may get away with pulling them off cleaning and regreasing.
Hope this helps.

 

[NeedMoreBoost]

Thanks bloke. Cleaning and regreasing won't help as that was done with wheel bearings and CV replacement a few weeks back. They looked ok from inspection then.

 

[happy john]

Did this problem arise after that work was done?.

 

[NeedMoreBoost]

No, I don't believe so. I had heard the clunk but not noticed the loss of drive. Hadn't been on hills as steep as when I discovered the drive issue though.

 

[dilmah]

Pull the hubs off and check the splines, check cv's for play or boots for damage, check front drive shaft, otherwise the front diff has stripped some teeth or snapped an axle shaft,if its not this then it will be the T/case chain

 

[bods]

Does it make any whirring/whining/other noises after the clunk happens before you reduce the load and regain drive?

 

[NeedMoreBoost]

Nah mate no other noises.

Constant load, single clunk and no drive. No other noise. Stop, reapply load, nothing until the next clunk.

 

[happy john]

Ok as I said previous the same driveline as yours 170k on the clock. Always in 4 low a steep hill bang loss of drive. Start again drive for 30 mins nothing get to a very steep hill off it goes again. Replacing the hubs fixed it.

 

[NeedMoreBoost]

Good enough for me. Which hubs did you go with, if I may ask?

 

[happy john]

avm I think mate it was a while ago.

 

[NeedMoreBoost]

Cheers. I was looking at those on ebay after your first post actually. No issues I assume?

 

[happy john]

Nothing sadly to my eye the original hubs showed wear but I cannot understand why they failed.

 

[dilmah]

Sounds like a front diff to me

 

[OneMofo]

Sounds like a front diff to me

Have to agree if its both hubs (so to speak) then it has to be something the drives them both.

 

[NeedMoreBoost]

Not with an necessarily with an open diff as I have. The wheel with the least resistance will get the drive. If one hubs slips so the only load on that side is the half shaft, it will spin the shaft instead of the other side, being shaft, wheel tyre and vechile. From in car it will feel the same as if it's been shifted back to 2wd.

Lock only one hub and have a play and see.

 

[bods]

I'd probably go with happy johns suggestion. I've never heard of too many problems with the genuine hubs, but I have used avms on a patrol I used to have with no issues. They have a lot chunkier locking mechanism in them compared to the spline setup the inside of the factory Nissan hubs have. Just don't put too much grease inside them as it can cause issues with locking and unlocking...

 

[Navmania]

Did you re grease the hubs with the service you did on them. If so you may have applied to much grease and created a hydraulic effect when the hub is engaged. So you turn the hub lock and it will move to lock but the internals don't move in to lock on the splines because they are spring loaded. Take some grease out and see what happens. They only need a small amount of grease. Cheers. Brad.

 

[OneMofo]

Did you re grease the hubs with the service you did on them. If so you may have applied to much grease and created a hydraulic effect when the hub is engaged. So you turn the hub lock and it will move to lock but the internals don't move in to lock on the splines because the are spring loaded. Take some grease out and see what happens. They only need a small amount of grease.

Cheers. Brad.

Thats a good point, people tend to pack the hubs with grease thinking they are helping.

 

[NeedMoreBoost]

You might be onto sonething Navmania. I packed a decent amount in there. Will pull a heap out and see how we go. Thanks!