87'wag

There was a thread close to this but I looked under my jeep and there is no vaccine lines. So the problem I am having is when I put it in 4wd it feels like it engages, but if you turn the tires with it engaged it dose not hoop like my 88 would if you engaged it on pavement to see if it was working.
1987 waggoneer
4.0L
NP242 is what the t case has stamped on the back of it
Automatic.
The 4wd elect pattern goes from 2wd-hi lock-4wd-N-low lock. Only 4wd light comes on when in the 4wd slot. On my 88 it would light up and say part time/full time ect, this one is different any ideas? I just put a remaned t case in it, front and rear u joints. Any help would be appreciated!

cruiser54

Hi-lock it will buck in turns, 4wd in green it won't.

Agent_Oragnge

the diffence between full time an part time 4WD is getting tiresome of being explained.

lookin2wheel

Ill answer this since it too aggravating for others to answer.......The reason it does not hop when in 4WD is because the center differential in the T case does not lock when you put it in 4WD. When you put it in 4WD Hi LOCK/ Lo LOCK, it locks the center diff and thats when you get the hop on dry pavement. Part time 4WD works like the Subarus sortof. Most of the power will go to the wheels with the most traction, usually the rear. When the rear wheels start slipping, power is sent to the fronts. Full time 4WD will split the power 50/50 front rear (LOCK Hi/Lo) and of course 2WD is just that, the front are "disconnected" and ALL power is sent to the rears. Hope this helps. Get it out on some sand put it in 4Lo LOCK, and punch it. If it leaves 2 trails of kicked up sand, your 4WD workd as advertised.

87'wag

Sweet i'll try that but it will probably be on snow, donno where to find any sand arround here lol thanks for the help! No indicator lights for high or lo lock tho?

87'wag

Haha im a desel engine mechanic drivetrain stuff is my weakness lol I did try putting it in high lock/low loc on pavement and it was the same feeling as 2wd when I turned the wheels, the only thing I felt chane was how it responded to the throttle. You know lower geared feeling

lookin2wheel

Ahhhh.....well that changes things a bit. Im wondering if you got another bad T case. I have read here that folks have lots of issues with the 242..... My Durango has a similar T case (Just no 2WD option). My XJ has the 231 so........

austinjoe13

Maybe the previous selectrac was like that? The NP242 locks up in PT or Hi-Lock in this guy's case and splits power equally and if one end slips you just hope the other end has traction. In FT or 4wd here the center diff is a torque bias. If you jack up a jeep on all 4 corners and put it in drive/reverse and full time you will only have one tire spinning, I know that because I did it. I'm sorry I have ocd for this, its a 48/52 split in torque in FT.Think of it as an ARB locker in the t-case.
Anyways, green can be used on the road, and orange will get wrecked on the road.

jebmccall

the front axle disconect?

87'wag

Orange? Only other light that comes on is red for parking break, crap lol at the shop they jacked it up with the olds t case and tires would move in the air bit put it on the ground and the front wouldn't. Im guessing because the rear had traction from what you said?

87'wag

I did look for yacc lines on the front axle there where non at all unlike my other cherokee s. How could it be disconnected?

cruiser54

NP242 transfer case equipped Jeeps had no front axle disconnect.

jebmccall

oh did not know that....

austinjoe13

Another reason why the NP242 is better!

99 Purple XJ

My 242 wont hop on dry pavement unless in 4 LO or part time