Coming out of four-wheel mode.

[KCJeep]

Just a quick question for the guru(s): When you go from 4x4 to 2x4 there is a lag before it pops out of 4x4 mode this is somewhat normal right? Ok, mine thuds a little as it pops out so any dangers to be looking for? I have driven other vehicles and when you go back to 2x4 it goes back it doesn't stay in till you hit a bump, brake hard, or it pops out a minute later with a thud. Is the selecttrack case any better besides the full time duty? Should it be pretty simple to put the selectrack transfer case in? Sure you have probably answered these questions a bunch of times but if you have kids you probably tell them the same thing over and over again right?

 

[tjkj2002]

I never had any lag from going from 4wd to 2wd with the 231 command trac t-case,then again it got used alot also which makes for smoother operation,no backing up or anything special was needed it just simply unlocked the front like it is supposed to no matter if I was going 1mph or 50mph.The 242 select trac can be a very tricky t-case for shifting since it is not a direct shift t-case,it uses springs and check balls which cuase havoc if all 4 of your tires are not within about 3%-4% total height of each other and may remain engaged for some time before the stress is relived and it finnally goes back into 2wd.

 

[Dave]

I never had any lag from going from 4wd to 2wd with the 231 command trac t-case,then again it got used alot also which makes for smoother operation,no backing up or anything special was needed it just simply unlocked the front like it is supposed to no matter if I was going 1mph or 50mph.The 242 select trac can be a very tricky t-case for shifting since it is not a direct shift t-case,it uses springs and check balls which cuase havoc if all 4 of your tires are not within about 3%-4% total height of each other and may remain engaged for some time before the stress is relived and it finnally goes back into 2wd.

Used a lot......... That is the key I think.

My 242 operates real smooth and is used a lot.

KCJeep. When shifting it try this....back off the gas......then shift it.....then back on the gas and it shold be smoother.

Change the t-case fluid. It is easy to do. I am not saying this is what is causing it but it won't hurt. ATF+4 is around $4.90 a quart at wallyworld so it will cost you around 10 bucks for 2 quarts.

Dave

 

[tjkj2002]

Oh yeah I forgot to add about changing the t-case fluid,I changed mine every 6k(every 2nd oil change) with ATF+4 since I heavily used my 4wd(mostly 4low).The ATF+4 would be just about black after 6k and heavy use rock crawling.Takes about 10mins max to drain/refill.

 

[JeepJeepster]

Yeah, once I figured out how to shift the 242 mine shifts perfect. Just cant shift then make an immediate turn. Best to be going straight for a few hundred feet. Mines been in full time for the past week and Ive not had to think about it.

 

[J-Thompson]

The problem is you are trying to make your Jeep into lumber instead of putting it into
2wd mode
The T-case should shift smooth and easy
frequent use and fresh fluid will make it better

Jeeps are 4X4 and 4X2
it is said 4 by 4 and 4 by 2 ,4 wheels driven by 2
2X4 is lumber

 

[KCJeep]

It physically shifts in and out with little effort and is smooth going in. What it does is stays in part-time for a little bit after when I shift out. I changed the fluid this past summer. When it does come out you can hear a little "thoomph" unless I am on the gas when it decides to shift out then it is more like a firmer "thumph" sound. Just wondering if there may be an problem with the disengaging part that I should be aware of like a precursor to failure.

 

[osufans]

mine does the same thing...like stated above...it helps to let off the gas and coast right after shifting out of 4wd.

also, just for comparison, my ford ranger did the exact same thing. so as far as i know, this appears to be normal behavior.

 

[J-Thompson]

sounds like you are doing it wrong
the process that works best with an NP231
drive forward slip trans to N
shift to 4wd ,if low then going less than 5 mph is advised
then back to D ,if off roading then put trans in lowest drive gear

all the delay and thumping is due to the bind caused by leaving the rig in drive

 

[KCJeep]

sounds like you are doing it wrong
the process that works best with an NP231
drive forward slip trans to N
shift to 4wd ,if low then going less than 5 mph is advised
then back to D ,if off roading then put trans in lowest drive gear

all the delay and thumping is due to the bind caused by leaving the rig in drive

So when I shift out of 4wheel the auto-trans should be in neutral? I think that kind of defeats the whole purpose of the on-the-fly four-wheel drive system huh? If you have to put things in neutral and so on then what's the point you may as well have manual locking hubs too. It has been doing this since obtained so I guess it's just normal. Warranty expires in about 8000 miles once I get to 80,000 miles so I guess it's just old age and will let it pass as it seems to have spring many theories and they all can't be correct. So as far as I am concerned class is dismissed.

 

[tjkj2002]

So when I shift out of 4wheel the auto-trans should be in neutral? I think that kind of defeats the whole purpose of the on-the-fly four-wheel drive system huh? If you have to put things in neutral and so on then what's the point you may as well have manual locking hubs too. It has been doing this since obtained so I guess it's just normal. Warranty expires in about 8000 miles once I get to 80,000 miles so I guess it's just old age and will let it pass as it seems to have spring many theories and they all can't be correct. So as far as I am concerned class is dismissed.

No need to take the trans out of "D" for shifting from 4hi to 2wd with the command trac t-case,only for coming out of 4low.

 

[Simpleman]

You only have to put it in neutral when shifting into 4Low, 4Hi is on the fly.

 

[J-Thompson]

do it in what ever manner you want
I do it like I stated and NEVER have shifting issues
231 in the TJ
231 in the YJ
242 in the KJ

 

[KCJeep]

Yeah 4low you have to be in neutral to shift in or out but I have never had to use that. I was only speaking of regular 4x4 mode 4hi. I will just let it go it works has been working and is just a little thoomph that I can deal with. I only wanted to know if it were a precursor to some failure that is on the horizon for me but I will deal with it when the time comes if it does. I spend more time in this rig anyway.

 

[family KJ]

I had a similar problem and as I was searching around under the jeep...around the t-case, I notice that I was missing a bushing that is attached to the linkage that goes to the 4wd shift lever. Basically, the plastic linkage was just slipping off the t-case as it had no bushing to hold it to t-case. A $3 part fixed what seemed to be a big problem!!!