Topic: XJ 4wd system (Read 3750 times)

lucky · « **on:** March 12, 2007, 16:42:51 »

Hi all,

I am currently looking to buy a Cherokee XJ. I used to off road a classic range rover but fancey a change. I have seen 2 different 4wd systems for the XJ on the internet. From what i cam make out one u can only use off road ( with a center diff lock ?? ) and the other where you can used the 4wd option on road.

Where both systems sold in the uk??

Is one better than the other for any reason??

Are either of the center diffs viscous??

thanks for any help in this matter, any other advice on what option / models are best, would also be much appreciated

Cheers
Lucky

Bishops Finger · « **Reply #1 on:** March 12, 2007, 17:13:11 »

If Im right..

For all XJ's ..

Diesels and 2.5 sports have a semi permanent 4wd system whch entails moving a lever to engage 4wd

The 4 litres have a different transfer case which means should you choose you can run in full time 4wd

Mort · « **Reply #2 on:** March 12, 2007, 17:20:48 »

Hi Lucky

The 2 systems are:-

Command Trac - as fitted to the diesels and 2.5l petrol (which all have manual transmission). These have 2WD, Part-Time 4x4 High Ratio and Part-Time 4x4 Low Ratio. Neither of the 4WD positions can be used on-road, as the centre diff in the T/C is locked - although you could use it in deep snow on-road, but with caution.

Selec-Trac - as fitted to the 4.0 petrol variants (which all have auto transmission). This offers all the above settings plus Full-Time 4x4, in which the centre diff in the T/C is open. This can be used at all times and in all conditions when on-road.

Other (hopefully) useful info:-

The diesels, 2.5 petrol and pre '97 4.0 petrol are fitted with a rear LSD. The Post-Facelift '97-on 4.0 versions are not. I believe that the Post-Facelift versions had galvanised bodies. They are certainly less prone to rust.

You can change between 2WD and Part-Time 4x4 (and 2WD, Part-Time 4x4 and Full-Time 4x4 on the 4.0) 'on the fly' at speeds of up to 55 mph. You'll need to stop when engaging Part-Time Low ratio. The T/Cs are old fashioned cogs and chains.

I'd go for the Selec-Trac on a '97-on Post-Facelift 4.0 every time - although the previous versions can be picked up for silly money - sometimes as low as Ã‚Â£800. If fuel consumption is an issue, then get one that's been converted to LPG.

Finally, don't be put off by the auto transmission. They are surprising good off-road (I prefer them by far).

lucky · « **Reply #3 on:** March 12, 2007, 21:04:57 »

thanks for the advice ,

thats a big help. Glad to hear the pre 97 has a LSD no more getting cross axeled :D

CaptainColourful · « **Reply #4 on:** March 13, 2007, 00:23:09 »

My 98 reg ( xj ?) 4 litre is fitted with yet another variation ... Quadra-Track.
This is a full time 4 wheel drive with low and high ratios, which are changeable at 2-3 mph with the gear selector in Neutral ( similar to Disco)
Trac-Lok rear axle is basically a limited slip diff.. There is no diff lock fitted to these models as far as I know.

tim_aka_tim · « **Reply #5 on:** March 13, 2007, 10:19:44 »

Quote from: "CaptainColourful"

My 98 reg ( xj ?) 4 litre is fitted with yet another variation ... Quadra-Track.
This is a full time 4 wheel drive with low and high ratios, which are changeable at 2-3 mph with the gear selector in Neutral ( similar to Disco)
Trac-Lok rear axle is basically a limited slip diff.. There is no diff lock fitted to these models as far as I know.

If your Jeep is the one in your avatar, thats a ZJ, not an XJ. Different beast.

XJ - 1984 to 2001 Cherokee
KJ - 2001 onwards Cherokee/Liberty
ZJ - 1993 to 1998 Grand Cherokee
WJ - 1999 to 2004 Grand Cherokee

Mort · « **Reply #6 on:** March 13, 2007, 14:09:08 »

Quadra Trac was never fitted to XJs, which is a shame, 'cos it's a good system. As Tim says, yours must be a Grand Cherokee.

IIRC the Quadra Trac system uses a gerotor in the T/C, which will automatically engage a clutch to to restrict the centre differential, without user intervention, if one prop shaft turns significantly faster than the other. There is also a Quadra Drive variant which has a gerotor in the front and rear axles too which operate when there is a significant speed difference between wheels on an axle - so you would effectively have automatic axle diff lockers. Neat system.

CaptainColourful · « **Reply #7 on:** March 13, 2007, 17:49:50 »

I stand corrected, thanks lads. Err yes it is a Grand Cherokee.

I knew there was "J" in it though :roll:

Looking through the owner's handbook, it mentions a Torque Converter Clutch, a feature designed to improve fuel economy. It engages automatically at calibrated speeds " and may result in a slightly different feeling or response during normal operation at high gear"
So you see ? The handbook is as clear as mud.
No wonder I am confused :?

Cherry Bomb · « **Reply #8 on:** March 14, 2007, 01:01:25 »

You have to remember that the manual was written for the american market, so has useful information like making sure the vehicle is stationary before exiting and not driving so fast it falls over.

Dinkydave · « **Reply #9 on:** March 14, 2007, 07:17:18 »

It covers them for eejuts behind the wheel. :lol:

Like the darwin award bloke who took a company to court because in the handbook of the winabago he'd bought it didn't tell him you couldn't put it in cruise & go & make a coffee.

He crashed (and won the case)

Not sure how true the story is, but it is the USA :lol:

UKJeeper · « **Reply #10 on:** March 14, 2007, 08:17:11 »

Its fake. (but funny :lol: )

http://www.snopes.com/autos/techno/cruise.asp

barttheguinnessguy · « **Reply #11 on:** March 17, 2007, 01:54:39 »

Quote from: "Mort"

Hi Lucky

The 2 systems are:-

Command Trac & Selec-Trac

I was gonna say that :roll:

lucky · « **Reply #12 on:** March 26, 2007, 10:08:23 »

thank u all for ur help

I have now got a cherokee,

M plate 4ltr

will be picking it up at the weekend

anyone know if my set of 235/75/16 will fit on it??

thanks again

tim_aka_tim · « **Reply #13 on:** March 26, 2007, 10:11:33 »

Quote from: "lucky"

anyone know if my set of 235/75/16 will fit on it??

Sadly not, MKI Cherokees have 15 inch wheels.

Snake110 · « **Reply #14 on:** July 17, 2007, 20:15:10 »

sorry to but in but have i read this correctly
my M plate early 95 i think (still waiting for logbook)

has an LSD rear diff ??

it definatly has selek trak

isle of man · « **Reply #15 on:** July 17, 2007, 21:43:00 »

possibly............but i would be very surprised if it is servicible, jack both wheels off the ground and check.

peter henry

Snake110 · « **Reply #16 on:** July 18, 2007, 23:45:42 »

Quote from: "isle of man"

possibly............but i would be very surprised if it is servicible, jack both wheels off the ground and check.

peter henry

ok next dumb question

im used to how/what happens with an open diff with one wheel up
what am i looking for in this case ?

UKJeeper · « **Reply #17 on:** July 19, 2007, 08:12:30 »

You will be looking for the other wheel to rotate in the opposite direction (weird but true) when you hand turn a wheel. Or get a mate to hold a wheel while you turn the other one, his one should also rotate. If it does these, then the limited slip diff is working.

The clutch plates in these factory LSD's do wear out, but are relatively easy to overhaul.

I also have an M reg Cherokee, and the LSD is working fine. I think all the UK spec 4.0 Cherokees had an LSD as standard.

Snake110 · « **Reply #18 on:** July 19, 2007, 10:26:07 »

right ill be checking that today then
cheers

Mort · « **Reply #19 on:** July 19, 2007, 16:28:12 »

Quote from: "UKJeeper"

I think all the UK spec 4.0 Cherokees had an LSD as standard.

Nope! :roll: As I mentioned above, post facelift ('97 on) 4.0 Cherokees do not have a LSD.

News:

AuthorTopic: XJ 4wd system (Read 3750 times)

Snake110

Snake110

Snake110