Whats up with my diff

[dan.c]

Hi

Recently brought a gen1 swb pajero. LSD in the back. When in 4wd low and turning, the back wheels skid like the diff is locked, however if a wheel comes off the ground it still spins and the other one stops. When in 2wd its barely noticeable, maybe a few shudders when turning sharply. Whats going on here?

Thanks

[The WEHI]

The Transfer case sends the same amount of drive to both front and rear so when in 4lo/4hi on full lock the front wheels need to travel differant distance to the rear so makes it bind usualy the wheel with least traction will release that tension. Which sounds like what you have descirbed

[The WEHI]

^ Make sense?

[suzolla]

That is normal of any 4wd vehicle.
When in 4wd front and rear are locked together and so at each end the wheels want to turn at the same speed, but when you turn the outside wheels have to travel further than the inside wheels but because they are locked something has to give, often the inside back as this generally has the least weight on it.
Cheers
Tim

[Crash bandicoot]

that's answered the question of turning in 4wd.

on a related issue, if your LSD is unlocking with the pressure easing off as the wheel leaves the ground it may be time for a rebuild

[dan.c]

I thought lsd still allows the wheels to turn independently of each other on the same axle though? This acts as if its locked, was driving along a slope today, turned uphill and it just continued to move forward... iv owned a fair few pajeros and l200's and none have done this.

I also thought that it was normal for a lsd diff to spin one wheel when one come off the ground and lockers were the way to fix this?

[churchill]

If the other trucks you were driving had center diff's this would effect their uphill turning ability.

By the way I wouldn't engage the 4wd system on tar seal or concrete unless its slippery as you'll wind it up and could damage something.

Could you have a mechanical locker in the back instead of an LSD? If it clicks and bumps it sounds like it could be a mechanical.

[Crash bandicoot]

LSD Limited Slip Differential emphasis on the limited.

with one wheel off the ground your rear diff is acting like a NON lsd

a LSD is designed to lock up when one wheel looses traction...see where this is going?

http://en.wikipedia.org/wiki/Limited-slip_differential

that may help

[dan.c]

yeah that makes sense, i was just quoting info i read off here...

no, never had a vehicle with a center diff.

think i have figured out why it handles strange (to me) though... turns out the front is lsd too, and i think the rear diff is on its last legs - every time i accelerate or change gear theres a nasty clunk - and its getting louder. i have a replacement diff, but have also been offered an auto locker - are these legal?

[Crash bandicoot]

yeah that makes sense, i was just quoting info i read off here...

no, never had a vehicle with a center diff.

think i have figured out why it handles strange (to me) though... turns out the front is lsd too, and i think the rear diff is on its last legs - every time i accelerate or change gear theres a nasty clunk - and its getting louder. i have a replacement diff, but have also been offered an auto locker - are these legal?

only locked differentials are frowned upon in a road legal vehicle.

whether it be a LSD, mechanical locker, auto locker air locker whatever locker as long as there is room for the opposing wheels to turn independently of each other for some period of time before locking there is no issue.