Transfer Case/Part time Light

OK all I have a 2001 Jeep XJ with a 231J Transfer Case i have a couple of questions i hope some you smart guys can help me with.


1. Is it normal that my front drive shaft rotates during 2h?

2. There are two sensors/switches on my transfer case (one on the front case and one on the back case) what are these and what are there purpose?

3. My amber "part time" light never comes on even when I'm curtain its in 4H because of the effect it has on steering on pavement. Does the sensors/switches in question 2 have anything to do with this?

4. Recently there is the sound of gears engaged which is consistent with driving speed. I know its not in 4H and can be heard best at 30 mph.

I would like to fix the problem myself so any input would be greatly appreciated!

OK with some more research i think i have found out that the sensor/switch on the rear part of the transfer case is the speedometer pinion sensor... so im going to assume that there is nothing wrong with that since i know how fast I'm going down the street.

And....

I have found that the sensor/switch on the front of the transfer case is a switch, "Transfer Case Mode." Is this what triggers the light on the dash... if i know that the bulb on the instrument panel is good is this an easy replacement?

For your first question, yes it is normal for all shafts to rotate. There is no hub or axle disengagement here, so the only disconnection is inside the transfer case.

You appear to have found the correct switch on the transfer case - the forward one. Before replacing it, it might be a good idea to check it with an ohmmeter at the connector nearest to the switch. There is a possibility that your problem is in the connector at the instrument panel or elsewhere in the wiring, rather than the switch, so you might as well make sure. If it is the switch it should be an easy screw-out/screw in replacement.

As for the "gears engaged" sound, hard to say. As a transfer case ages, it can get a little noisy. A fluid change might be a good idea. You might also have a look at the universal joints on the driveshafts, a possible source of drivetrain noise.

I have checked all fluid levels; changed the transfer case old a couple weeks ago; changed the rear differential fluid a couple days ago but i didn't do the front diff. because i thought if i don't use 4WD often then the gears don't turn in the axle (guess im wrong, however the fluid was changed less then 40K ago), and I'm sure all the correct fluid was used.


I don't know if this makes the situation any different but i had recently took my truck to the dealer for service under a powertrain warranty for a leak in the front pinion seal (@66K, 09/06/06). They replaced the front pinion seal and yoke, do you think they could have screwed it up? I'm now at (67K, 09/27/06). If its something i can put on them i can get out of another $100 dollar deductible. This is the first time i realized how little miles i had put on it since then.

the easiest way to diagnose your front drivetrain noise is to pull the front driveshaft.
If the noise remains then it's in the front differential. If it goes away then it's in the driveshaft or the front TC output.

Matthew Currie said:

For your first question, yes it is normal for all shafts to rotate. There is no hub or axle disengagement here, so the only disconnection is inside the transfer case...

Click to expand...

Not to hijack this thread, but when my '94 ZJ (w/NP242 transfer case I believe) was up on a lift getting an oil change, the guy grabbed my front drive shaft and said "This thing should rotate freely--it doesn't--I'd disconnect it if I were you" as he said it was impeding my normal 2wd operation.

So now I'm confused--if the Jeep is in 2WD, the front axle should NOT rotate, right?

With my power-train warranty I took my Jeep to the dealer in hopes to get to the bottom of the problem... They told me they are going to rebuild the front axle and transfer case... (I'm not crazy after all). I do little off roading, sorry guys, and this happens at 67K. I guess i didn't get the luxury of having a die-hard jeep. If this happens again after 80K its out of my pocket, so I hope they do a good job. I will let everyone know more details when i get it back later next week.

laserfan said:

Not to hijack this thread, but when my '94 ZJ (w/NP242 transfer case I believe) was up on a lift getting an oil change, the guy grabbed my front drive shaft and said "This thing should rotate freely--it doesn't--I'd disconnect it if I were you" as he said it was impeding my normal 2wd operation.

So now I'm confused--if the Jeep is in 2WD, the front axle should NOT rotate, right?

Click to expand...

no, and that's why that guy was doing an oil change and not rebuilding and engine somewhere.
after 93 there were no disconnects in the front. SO the axle turns all the time.

87manche said:

...that's why that guy was doing an oil change and not rebuilding and engine somewhere...

Click to expand...

Well, that's why I thought I'd better check his information before pulling my front driveshaft off! 'Course I'm not sure I should trust a guy on the www either!

Thanks for the quick feedback... :worship: