• Welcome to the new NAXJA Forum! If your password does not work, please use "Forgot your password?" link on the log-in page. Please feel free to reach out to [email protected] if we can provide any assistance.

4lo questions

T

targetslayer

NAXJA Forum User
Location
Denton, Texas
I have a 99 XJ, 4.0, auto, NP231. I have taken this jeep on some expeditions, handles great on trails and mud, never any problems, but have never required the use of 4lo. Today I went wheeling with a buddy, we did some very steep hills, rocks, and very uneven terrain. Initially it went into 4lo very easily, performed great, but everytime I tried to get out of 4lo back to 4hi, it got progressively harder, and sometimes grinding. Now it is very hard to get into 4lo, and takes alot of effort and wiggling. I did go through a bunch of water and gunk. Other than that it was awesome performed better that I expected. Could there be alot of crap jamming up the transfer case, or what could be other possible problems?
 
Check the linkage underneath. The stock setup isn't that great.

Did you try backing up to help it shift?

Which t-case? Trans? Year?
 
I did try going in reverse too. It went in and out of 4lo everytime, it just got progressively harder. It is in 2wd now. Just never having used 4lo before, I didn't know what to expect, or how it would feel, or anything about it really.
 
How are you shifting into/out of 4lo? With mine it says to shift into/out of 4lo while moving at about 5mph and the transmission in Neutral. For me it works every time and is smooth with a nice decisive pull/push on the lever.
 
Was doing the 5mph thing but was not in neutral. I would be going 5mph and do the shift from 4hi to 4lo, and same to come back to 4hi. Did not realize I had to have the transmission in neutral. Hope I didn't jack anything up.
 
With an automatic, anytime you try to shift from Low to High there is the possibility to have the gears scratch or not go into High at all. I always shift to N if I want keep moving and maintaing less than 5 MPH. The other way is to come to a complete stop, shift the AW4 to P then shift the lever back to high.
 
Linkage could be loose.

I always shift in and out of 4lo when the trans in N, and at a stop. Never had an issue. But once I'm in, I stay in until I'm done for the day.
 
That's what I am learning, I really should have just stayed in 4lo. There really was no sense picking and choosing. Definately next time I will put it in low, and stay that way to the end. Thanks guys.
 
You should only go a certain top speed in 4lo though, I don't know off hand but it is not that fast if I remember. I never really needed 4lo so far, I've only put it in a few times just to test it out.

Also, I think the idea of moving around 5mph is to give the gears a chance to mesh. If you are at a dead stop the gears aren't moving and won't have the chance to mesh instead of being forced.
 
You. Will want to get out of 4-low if you have to travel a considerable distance to the next obstacle. Using low range creates extra heat in the t-case, which cooks the Dex III, which, you guessed it, makes it shift worse.

Have you ever checked /changed your fluid? If not go pull the fill plug and dip a finger in, if it comes out black, the fluid is toast.
 
I never had any problems with TC heat and wear using 4 low. Granted, I never did that much off roading, but it's practically mandatory with a stick shift and its tall drive ratios, and whenever I've gone any further off road than a local dirt road, I've generally put it in low and driven it in second through fourth. It's a good deal easier on the clutch that way.
 
Yeah, its a neccesity with a stick. 3rd in low is roughly equal to 1st in high, so having those two deeper gears really helps.

The heat thing might just be conditions as well. I do most of my wheeling in the desert/rocks. Better part of the day moving at slow speed.
YMMV
 
You must log in or register to reply here.

Similar threads

O
2000 XJ Failed Colorado Emissions high CO
2
Replies
27
Views
2K
Ken M
K
F
Drum Brake Damage - Post mortem?
Replies
16
Views
3K
RCP Phx
R
S
No Start No Bus
Replies
16
Views
3K
Rob Mayercik
R
U
Overheating? Quick help please.
Replies
9
Views
2K
75SV1
7
9
P1694 P1698 P700 codes - did all the tests?
Replies
6
Views
2K
Unclewolverine
U
Back
Top