Outer Limits 4x4 Board

My GQ

when load is put on front wheels while in 4wd a loud knock can be heard and felt from under the car (can't pick which side the sound or knock is coming from) when this knock happens the front wheels lose drive for anywhere from a few seconds to a few minutes. Drive then returns. I say it happens when load is applied but what i mean is, when more than just driving straight. If i'm driving straight on flat in 4wd then no dramas. But as soon as I put the right foot down heavy i get the reaction. Also especially when using the gears to slow me down going down hills I get it quite regularly. As i dont have a Front locker i can't see if any wheel in particular is being affected.
no problems till 4wd is engaged. in hi range and low. with 2wd engaged and hubs locked no dramas

Also dont know if it's related, but on a slight incline with car turned off and no park brake applied the car seems to struggle to hold itself still and not roll down.



Is a hub popping out? is the Transfer case dying? any ideas ?

My guess would be one of the hubs, but that's not the only possibility... it's just where i'd be starting.

Jason

might try and get a spare hub from wrecker tomorrow. I dont know which one could be rooted. I swaped right to left with no change .

Nnnng diagnose it before you spend money!

how do diagnose if it's the hub or not?

I think you need to jack both wheels off the ground then lock both hubs in and spin a wheel at a time. It could be a little circlip has come off the end off the problem axle so you will need to alon key off the hubs and check. The hubs dont like Greas or to much.

circlips on hubs are fine, as i've taken hubs off many times to check the clips and they are still holding it all together. No grease or oil in hubs.

lifting both front wheels however does something strange. You'd think that when you spin one wheel the other wouldnt go, but it does. Strange because i dont have a locker, i was under the impression that when unlocked the wheel you spin should spin while the other dosnt. Strange because when driving the car with 4wd the steering is fine and dosnt feel tight like when there is a locker engaged.

ideas?

YankeeDave wrote: i was under the impression that when unlocked the wheel you spin should spin while the other dosnt.

Not exactly... If the front axle is NOT allowed to spin (4WD selected and handbrake on etc.) then if you spin one wheel the other wheel SHOULD spin but in the opposite direction.

If they are the Auto hubs with the manual over-ride I will wager that is the problem.
Jack the rear off the ground and put on stands for safety.Chock the front wheels and let the clutch out gently in 4wd.If the noise is duplicated and the vehicle is safe,ie not trying to move away,have someone check where the noise is coming from,ie is the front shaft turning or is the noise at a wheel.
J Top

Check the transfer lever is not loose on the shaft that goes into the transfer case--maybe its not engaging 4x4 properly--OR make sure freewheel hubs are not overpacked with grease. Also check that the front axle shafts dont have excessive end-float--this is normally set by the thickness of the snap-ring on the end of the axle shaft

Nick

id say its the hubs i done a set on the gq axles i got under my lux the other weekend.....

Had same problem and it was hubs.
Changed them both and noise is gone and I have drive to front wheels now.
GU auto locking hubs are known to give way.

have a similar problem with an MQ and i was told and suspect it will be the hubs