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4wd wont engage

totalvideo2

NAXJA Forum User
Location
port orchard
88 xj np 242 tried to put in 4wd and wouldn't go into full time, stuck in part time and when i turn grinding noises coming from front of jeep. need advice
 
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.

"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, and then tap the gas and let off.

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".
 
Lift the front off ground, Put it in 4wd and crawl user and try to turn the front driveshaft. With the trans in park. If it turns the grander add is not engaging. If it doesn't turn most likely you vacuum actuator for your disco axle is either not getting vacuum or is dead.

The grinding is it when you try to use 4wd and turn or in 2wd. If 2wd check your u-joints. Same in 4wd but in 4wd also the collar for the disco axle might be just on the edge of connecting. But also if you can turn the driveshaft in the test above when in 4wd and in park the transfer case is trying to catch but can not.
 
Lift the front off ground, Put it in 4wd and crawl user and try to turn the front driveshaft. With the trans in park. If it turns the grander add is not engaging. If it doesn't turn most likely you vacuum actuator for your disco axle is either not getting vacuum or is dead.

The grinding is it when you try to use 4wd and turn or in 2wd. If 2wd check your u-joints. Same in 4wd but in 4wd also the collar for the disco axle might be just on the edge of connecting. But also if you can turn the driveshaft in the test above when in 4wd and in park the transfer case is trying to catch but can not.

NP242s don't have disco.
 
I was driving down the road at 25 let off the gas put transfer case into full time and tapped the gas, the indicator light on the dash only went to part time. While in part time the 4wd was not engaged so i tried to move the transfer case back into 2wd, the indicator light was still showing part time and when i made a turn there was a grinding noise coming from the front of the jeep. I was able to finally get the tranfer case light to go back to 2wd by driving around and letting on and off the gas several times but the whole time the 4wd was not engaged.
 
Unless someone did a front axle swap or a transfer case swap, the 242 transfer case didn't come with a disco front axle...should be no vacuum connection to the axle. Are you talking about the axle tube breather (on top of the axle)? The breather should have no effect on 4 wheel drive engaging. How long since it last worked that you know of?
 
Has to be about a year since it was in 4wd drive it everyday in 2 wd and no axle swap, was wrong about vacuum line it was the breather hose that came undone my bad.
 
Also a couple of months ago the vacuum line had come off the front axle and i just re-attached it, havent put the jeep into 4wd since yesterday.


What "vacuum" line? NP242 equipped Jeeps don't have a vacuum disconnect front axle. Sure it wasn't the vent hose on the driver's side of the axle you put back on? The CAD has a three hose harness to it on the back sie/rear of the front axle housing.
 
How are you checking to see if the 4wd is working? I read you were driving it down the road @ 25 mph? I've shifted into 4wd without my light being on however 4wd was still engaged.
 
Check the 4x4 shifter linkage, adjust if necessary. As for the grinding noises usually I have experienced binging, popping and hopping when in part time on drive pavement.

Also, didn't some early XJs some with the 229 and a vac disconnect?
 
Check the 4x4 shifter linkage, adjust if necessary. As for the grinding noises usually I have experienced binging, popping and hopping when in part time on drive pavement.

Also, didn't some early XJs some with the 229 and a vac disconnect?
84 rthrough 86 had vac disco with part-time t-case and without if full-time.
 
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