4WD engagement
 

Just a quick question, to get into any 4WD, do you have to be moving or can you be stationary?

I just reversed into a bit of a muddy patch (now out) but could not get any 4wd to engage. As soon as we pushed it a little and it drove out, 4 wheel full time engaged.

It depends on what 4WD system you have in your Jeep... Is the the Command-Trac? or the Select Trac (I think it's called - because it allows you to be in 4WD all the time even on dry pavement)
The Command-Trac system is part-time basically (on command hence the name) type. Which I believe the vast majority of XJ's had.
With that system you need to do the following for 4WD Low:
1. Slow the Jeep to about 5 kms per/h and take your foot off the accelerator pedal.
2. Move the automatic gearshift lever into Neutral
3. Then move the Transfer case lever from 4WD High
4. then move into 4WD Low
5. then still with foot off the gas...move the shift lever back into "D" Drive and boom you're in 4WD Low.

Now if you just want 4WD High ( you don't have to shift the transmission into neutral first.
Just remember that our Part-time on command systems (Command-Trac 4WD) can NOT be used on dry pavement without destroying your transfer case.

Does help to be moving a bit.

http://cruiser54.com/?p=117

Since you mentioned full time 4x4 then I am assuming you have the NP242 transfer case. Yes they have to move a little bit for the 4x4 to engage, if your stuck in 2wd shift into 4x4 and rock it back and forth between drive and reverse to get it to engage. An NP231 will engage almost instantly when you shift into 4x4 but the 242 is a little bit slow to engage.

If you have the NP242, from my experience, its about 100 times easier to engage any mode of 4wd (or get out of it), by first placing the auto trans (if so equipped) into NEUTRAL

( I know the manual says you can engage full-time 4wd on-the-fly, and you can too, its just MUCH easier to do it with trans in neutral)

The trick is to not have any load on the drivetrain, even like being stationary in gear. Shifting to neutral in the transmission removes that load. The t/case is not synchronized, so gear teeth have to be matched to shift.

Thanks all. I may have to get stuck again and try out a couple of ways to get it to engage.

Only last weekend I was laughing at my friend in a MX5 Mk1 getting stuck on a rock, this weekend he's laughing at the 4x4 getting stuck and not popping into 4wd.

CRUISER'S MOSTLY RENIX TIPS

SHIFTING THE TRANSFER CASE

NOVEMBER 17, 2015 SALAD 8 COMMENTS

Here’s how the factory suggests you shift the transfer case and I’ve been doing this since these things were new and I worked at the dealership. Quoted from the owner’s manual. The suggestions in BOLD are mine.

“To engage, shift the transfer case lever from 2H to 4H while the vehicle is moving at any legal speed”. I let off the gas, throw the lever, tap the gas, and let off again.

4L position: ” To engage, slow the vehicle to 2-3 MPH , shift the transmission to Neutral, then shift the transfer lever to the right and pull firmly rearward to 4L”.

To shift out of 4L, stop the vehicle, shift the transmission to Neutral, shift the transfer case lever to 4H, then the transmission to Drive (if you have an automatic), or First gear (if you have a manual), and continue on.