Subsonic Dues

My cluster says Part Time when i engage my 4x4, so i am wandering if i can make it a full time and how.

FruitSnacks

What does your transfer case shift lever look like? does it have a "full time" option?

Subsonic Dues

2 Hi
4 Hi
N
4 Lo

XJlimitedx99

Part time indicates that the front and rear driveshafts are locked together, always turning at the same speed. That's why it should only be used "part time."

Jeeps with the np242 TC have a full time option that only engages the front driveshaft when the rear beings to slip. It is okay to use it on dry pavement or "full time."

So basically it shouldn't light up full time, because you don't have the full time option with your np231 tcase.

FruitSnacks

Exactly

Subsonic Dues

But can i make mine full time?

jmm0122_

Not without swapping out the transfer case. The full time option is only available on the NP242 and you have the NP231. The part time means its only active when you engage it ie 4 high or 4 low. You shouldn't drive around all the time with it in 4 high or 4 low since this will cause damage to the transfer case. If you had the NP242 with Full time option you could just leave it in 4x4 all the time without doing damage.

Subsonic Dues

But thats it? just the transfer case?

FruitSnacks

Transfer case, shift linkage, shift bezel. Might be a couple more pieces I'm forgetting...it's still early lol

jmm0122_

I believe driveshaft's would need to be swapped as well. But honestly why do you want to swap yours out? A little more background info on why you want the full time option would be helpful.
Most XJ's come with NP231's so why go through all the work of swapping to an NP242?

thatXJguy

Yes I do believe a driveshaft is necessary too. I think one is shorter than the other.

I love my factory 242.

jmm0122_

I've never had an XJ with a 242, but is it really worth the hassle of swapping if you already have a 231? I just don't really see the benefit of a full time 4x4 system. Enlighten me please

SteveMongr

Please allow me to clarify. The 242 has an internal differential. It splits power between rear and front drivelines (Like 52 rear / 48 percent front). During normal driving, when all 4 wheels have traction, it is always powering the front driveshaft when 'Full-Time' is engaged.

In FullTime, if you pull up to a step type obstacle with the front tires and try to crawl up it, power will be redistributed to rear while center differential turns instead of front driveline. Opposite in reverse with the rear axle.
In other words, front wheels will not 'power' up and over the obstacle, center differential will turn instead.

Subsonic Dues

Im sorry guys i know im sounding like a tool probably with all my short question/answer bs. I bought my jeep as a family vehicle/ DD. I have 3 boys (6,5,3). I took them Wheeling yesterday and among the lengthy list of stuff i want to do to my XJ, i was reading and it would seem that Full time 4x4 would be the way to go and i figured it would be easier to change it over than replace the one i have when it breaks. Plus im in the National Guard and want to make my XJ as close to our Up Armored HMMWV's for fun. We have them set as full time 4x4 and that is another thing that made me want to change it.

thatXJguy

I love my 242.

I would always want a 242. I run it on the roads often when Florida has its torrential downpours and it keeps me from spinning tires, while still keeping halfway decent speeds. The handling aspect is much better.

The Full Time option basically makes an XJ like a Diablo in terms of handling.

Some people run part time with their 231s on the roads, but I never ever recommend this. Even the factory manual recommends against this. Since you have very limited slippage and your two axles (front and rear) are basically synced together, you could break something doing this if you're not careful. This is the beauty of full time... you can just drive normally.