Markp UK

Hi there!

I have a UK 2000 XJ 4.0, which is unmodified. The car spends most of it's life in 2wd mode and has experiences no symptom in the mode.

Today I put it into 4wd mode due to icy conditions. After about 10 miles of mixed driving I found the front wheels started to bind really badly and skiding, when the wheels turn on full lock. Looking under the car there is no evidence of the wheels or tyre scuffing on anything, which is how it feels. After reversing the car in 2wd on both locks the issue clears itself and it's back to business as usual. Unless 4wd is engaged when the problem reapears.

I've recently replaced both front hubs, discs etc and rebuilt the calipers. I checked the front driveshaft joints and they had no excessive play in them and everything else appeared in order.

Does anyone have any theories on what could be causing this? Any help would be greatly appreciated!

Best regards

Mark

sthon

Were you in full time 4x4? If you only have 4 hi and 4 lo you don't have full time 4x4 and you shouldn't be using it on paved roads.

RenegadeT

which transfer case do you have...SelecTrac (NP242) or CommandTrac (NP231)? The 231 won't tolerate any pavement driving in 4wd, and will act exaclty as you describe.

Markp UK

Hi there,

Yes it was in full time 4wd.

Thanks

Markp UK

Hi again,

I don't know which transfer case I have, but the instructions on the sub visor state that full time 4wd can be used on any surface.

sthon

It shouldn't be binding in full time. When was the last time you checked your front diff fluid?

wiggles

In 2wd the tc acts like a differential, it let's the front and back spin at different speeds. When in 4wd it locks the front and back together in the tc. When you turn really sharp the front and rear tires take two entirely different paths so it binds in the front a little because the same amount of power goes to the front and back

Markp UK

I have to admit I haven't checked the fluid level. Would the lack of fluid cause this or is the TC shot?

Thanks

captainwoot

Does your 4wd shifter have: 2wd, 4pt , 4ft, n ,4lo (this is a 242 select trac) and when in full time (4FT) can be used on any road surface. Or does it have 2wd, 4pt, n, 4lo ? this is a command trac 231 case, 4wd can only be used under conditions that wheels are allowed to slip.
Hope this helps

Markp UK

By the sounds of it I have the 242 selectrac.

One thing I did forget to mention is once this has occurred it continues even if the car is put back in 2wd mode. The only thing that seems to clear it is reversing on both locks.

captainwoot

Sounds like maybe the linkage is out of adjustment, maybe not going into 4wd full time?? will it go into neutral and 4lo? Ifit does happen to bind up, somtimes reversing is the only way to free it up.

sthon

The 242 can be a pain to get out of 4x4. I usually have to drive it in reverse to get back in 2wd.

Markp UK

So would this mean that the car is only going into part time 4wd and the sticking there, even if the lever is put back onto 2wd, until the car is reversed?

DFlintstone

Quick question. Do you have the same size tires front and back?

Markp UK

Yes! They're standard tires!