97jeepxj40

Hi Guys

I'm hoping someone here can shed a little light on a problem I have.
I have a 97 XJ, NP242. When I engage full time 4x4 I get a constant grinding noise coming from the transfer case. I have searched and read a lot about this, but other people report various other symptoms with their grinding.

I have put up with the grinding for a short while now, but I set off out tonight in the Jeep, put it in FT4x4 and attempted to turn off my street into a main road. The Jeep was bucking and the wheels were hopping, it almost felt like the front wheels were pointing in opposite directions. I had to reverse a little and re-attempt the corner as I felt that if I continued something was going to break/snap; not only that but I had another vehicle coming toward me in the other lane that I was straying into trying to make the corner. I put the Jeep back into 2 wheel drive after this and continued as normal.

I'm not too sure at this point whether the issue is with the transfer case, bearings, U-Joints or something else - maybe even all of these issues apply.

I did try again putting the Jeep in 4x4 later in the journey, it was still making the grinding noise but I had no problems going round corners.

Has anyone any idea what this is likely to be?

I'm aware of the part time 4x4 - this shouldn't be used on dry surface due to binding etc, maybe full time isn't engaging properly? Speaking of which, when I pass through part time 4x4, the dash light for part time illuminates and goes out when I enter FT4x4, however the FT light doesn't illuminate.

Any help appreciated.

00jeepXJ

ok... from the sounds of it your transfer case has some problems. It sounds like the device that splits the power from front to rear is going bad. My real question is why are you running it in full time right now? Is there still snow by you? If it doesn't make that noise it 2wd then put it into that and leave it for now while you start looking for the parts. I hope this helps.

Markp UK

Hi, my XJ, which has the same transfer box, does exactly the same thing.

When engaging FT it gets stuck in part time. If you reverse up 50 yards it frees it up and it engages as it should, then you can continue. Apparently it's a common issue with these boxes.

I have just got used to backing up when I need to engage FT. Hopefully one of the more knowledgable guys on here should be able to advise on how to fix it.

Best of luck!

97jeepxj40

Thanks for the replys guys.

Interestingly, I had read on other posts that reversing helps it engage, I too have found this works. Just a few yards in reverse and then continue forwards helps. Same can be said for putting the Jeep back into 2 wheel drive.

I'm almost at the point now of removing the front drive shaft and putting it into FT. If the grinding persists then I guess the issue is with the transfer case. I hate to think what the grinding actually is. If it continues I think it's time to pop open the case.

As parts are few and far between here in the UK, I hope it's nothing major.

There is no snow, I have just been told every now and then to engage 4x4 to prevent locking up due to lack of use. I do try to do this, but I hate the noises it makes.

00jeepXJ

while engaging it once in a while to make sure it still works and isn't locked up did you do it on a dirt road or in grass? It helps to prevent undue strain and stresses on the transfer cases from being on dry pavement. As far as having to back up to engage and disengage the transfer... I would look at adjusting your linkage and that might help you. With my xj i had to adjust it after i bought it and after i installed the lift.

97jeepxj40

I have to confess to only engaging FT on dry pavement, however I was under the impression that the NP242 was capable of this without issue.
Thanks for the linkage suggestion, I will look into this.

I guess it would have been helpful if you didn't have to pass through part time to get to full time, but that's just my ignorant non-mechanical mind

00jeepXJ

don't feel bad. Once you start working your jeep you will start to hate engineers. I was always taught that the 242 could run on dry pavement in full time... however i just don't care and won't do it. I don't want to risk it.

N20jeep

The full time option is made for dry pavement use