Terrible noises in 4WD...what are the signs of a bad Transfer case?

I talked to my local transmission shop and asked him what could be causing the noises when i put my jeep in 4wd Hi or Low. I explained to him all mounts and control arms are new, and that whenever in 4wd it sounds as iff something is going to break!
I cant really explain it but when in 4wd, the front of the jeep makes horrible noises almost as if it want to come out of 4wd. am i doing something wrong?

He says he'll take it for a test drive later this week but he thinks its a transfer case or the chain inside is bad. I asked him what it would take/cost to rebuild it but he said not worth it, easier to pay $500 and get one from a local yard.

can anyone relate to this>? maybe even list signs of a bad transfer case?
I have new oil in the case and trans. and the lights come on when in 4wd.
the jeep has 250k on the odometer.

How hard is replacing the t.case? I'm not really looking for a crazy upgrade, mainly street driving but bad snow here in PA wintertime and since its coming up i'd like to be able to use my 4wd.

Oh yeah, what else could this be? possible suspension problems???

To get an answer that is more than just a wild a$$ guess you need to be very specific in your posting.

Besides the control arms what else on your Cherokee is not exactly like stock ? What sound(s) do you you hear? Describe it. Is the sound coming from the front or from from the middle or rear of the Jeep ? Does the noise change speed with speed of the Jeep or stay the same all the time? Happens in forward, reverse or both? Feel anything is the steering wheel ? Feel anything in the floorboards ? What have you checked underneath ? Are you trying to engage 4x4 on dry pavement ? What transfer case do you have ? What transmission ? What year is your Cherokee ?

Add any other info that will help.

Used transfer cases usually start at about $150.

It's hard to be specific because i am driving it on pavement/dirt road.
the jeep is a 94 xj 6cyl, automatic, sound seems to be coming from front of vehicle but could be from middle. NOT the rear.

New items are:
new solid adjustable control arms: upper and lower with solid bushings
solid engine and transmission mounts
solid endlink bushings
solid swaybar bushings
new trackbar with solid busings on it.
new steering dampner with solid bushings

I believe the case is a NP231 however i will double check as i know my 90XJ is the np231

double chkd. it is a np231 t.case

"what are the signs of a bad Transfer case?"

They smoke, drink, and get your daughter pregnant in the backseat of a Jeep.:firedevil

ItZaJeePThiNG said:

I talked to my local transmission shop and asked him what could be causing the noises when i put my jeep in 4wd Hi or Low. I explained to him all mounts and control arms are new, and that whenever in 4wd it sounds as iff something is going to break!
I cant really explain it but when in 4wd, the front of the jeep makes horrible noises almost as if it want to come out of 4wd. am i doing something wrong?

can anyone relate to this>? maybe even list signs of a bad transfer case?
I have new oil in the case and trans. and the lights come on when in 4wd.
the jeep has 250k on the odometer.

Click to expand...

I can relate. I came to the OEM thread because my rig is doing exactly the same thing after running Jenny Creek here in Colorado...

Yeah need more description of the problem, but my NP242 was making a hell of a noise and would jerk when I tried 4 wheel HI, LO, anything but 2wd.

It was the chain. It was streached so far that I was able to remove it without removing the gear first.

I bought a chain, $110 and a oil pickup $5. Works great. (Oh and about 12 hours of my time to replace the chain, but that was my first time breaking open a transfer case)

I tried to find a used NP242. I couldn't find one at a good price. I wanted to swap in the used 242 and then rebuild my original 242, put the SYE on it, etc...

You might try that, just get a used 231 and then rebuild the old one as you have time.

say for example it was the chain. can this be replaced without removing the case from the vehicle? what is all involved that it may take 12 hours to change a chain?
what all is needed to be removed to remove the t.case? say if i had to do this at a u-pull-it.

im going to try and take a short video of whats going on. My brother has my digi so when he gets back tonight or tomorrow i'll post it.

Replacing the chain does not require removal of the TC. I just did an SYE and left the TC in the vehicle. I'm sure it helped that I have a 3" lift and 1" TC lowering kit.

Just remove front and rear driveshafts, disconnect speedo and other electrical stuff, then the output shaft cone and front output yoke. Then the speedometer housing. Then a snap ring, and the rear half of the TC. Then the front and rear shafts will slide out with the chain.

Sounds easy, right? Well, it does take a while...but is worth the savings.

Give it a try.

well i passed inspection yesterday and washed detailed and cleaned the entire jeep today. i came home opened my door and down shel fell.

somehow the freakin hinges on the drivers side door just broke! wtf. So i put my daughter to sleep and went back out. i ended up welding the hinges back together and i'm going to the yard tomorrow for a few things, i guess a couple hinges are gonna be added to the list.
has this ever happened to anyone? is it common? i saw an episode on Trucks and they talked about this and fabbed up a new hinge but i never thought it would happen to me!

bump

I havent took a video of the noises yet but today when i went fishing i tried 4wd hi just so i could go over a little pile of rocks, as soon as i accelerate it makes a terrible grinding noise and you can tell it's bad.
i was not turning, i was going straight maybe 2 or 3 feet. the noise seems like it's coming from the front or directly underneath me, i cant tell.

Is it a grinding noise or a hissing noise?

It may be that the front DS is bad .

ItZaJeePThiNG said:

It's hard to be specific because i am driving it on pavement/dirt road.

Click to expand...

ItZaJeePThiNG said:

double chkd. it is a np231 t.case

Click to expand...

open it up yourself, its not that hard just get two good pairs of snapring pliers and have at it, its really not that bad.


fyi- dont run your 231 on the street

well its not a hissing noise but sorta like a grinding noise. I dont let it happen for more than a few seconds for fear of totally breaking something.

My haynes manual states if noise in 4hi 4lo but not in 2wd then problem is with front differential. possibly u-joints.

My joints are stiff & no play, the diff i just replaced the lube and when i drained it it had no metal inside and i also brake cleaned the inside until dry, this problem was apparent b4 the lube job:lol:

I dont understand how a bad "driveshaft" up front could be the problem because isnt it always spinning even in 2wd? oh wait maybe i mean axle shafts?

when i first got the jeep i did a complete overhaul on fluids, the t-case i probably drained out ah id say 3-4 maybe 5 ounces. yes it was dry. i even had the front end jacked up and nothing else was coming out. not to mention it was darker than dark.

I do not want to do the transfer case myself, however experienced I may be this is now a time situation and I just dont have it now that I'm starting a new job next week.

I heard a loose chain in the case could be causing the noise and its grinding on the teeth. how close is this a possibility?
How much money are we talking when having a shop replace the t-case as apposed to re-building it? with 250k miles is it worth rebuilding?

btw, i was thinking of jacking entire jeep up and have someone put in 4wd while im underneath and see really quick what it could be. I've done this many times in 2wd but never in 4wd for fear of the same reason you dont drive in 4wd on dry road. can i do this or will something break?

ItZaJeePThiNG said:

btw, i was thinking of jacking entire jeep up and have someone put in 4wd while im underneath and see really quick what it could be. I've done this many times in 2wd but never in 4wd for fear of the same reason you dont drive in 4wd on dry road. can i do this or will something break?

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Uh, the only reason driving on pavement in 4x4 is bad is because the tires have too much grip and it'll bind. If you jack up every wheel and put it on four jackstands, all wheels won't have any grip and you will have absolutely no problem running it in 4x4.

feel your driveline, pop the cover off you front axle and take a look at things also just lay down under your jeep for a while and look long and hard at everything if nothing seems wrong and the gears in the front axle are good it's prolly the t-case. and they are very easy to change if your cookin 1hr. job take out the drivelines then pry the shift linkage off the t-case side then using a jack take out the four crossmember bolts and lower it down then remove the 6 mounting nuts and slide it off the back of the trans. if your a sissy lol have a buddy help you pull it down one guy can do it but if you have never done one it better to have help. don't forget to drain it first or hold it level when you pull it. unless you like to be covered in atf. their is only one way i know to learn how. and thats to do it.

I am bumping this thread because I tried my 4wd today and i did actually run with 4wd high on the icy roads of pittsburgh. it still makes terrible noises especially when making turns. I know that turning while in 4wd makes some noise but this is not normal i can tell.

my u-joints are solid and have no play. I may have a bad balljoint because i do hear a knock on right turns every once in a while. every zerk fitted part is greased and all lubrication is topped off full.
Today was the first time I actually said screw it and ran the 4wd. hear is what I noticed, turns make the crunching noise, moving from a stop in reverse or forward will cause the noise, cruising doesnt make the noise however if i accellerate hard while rolling it will make a small noise.
stopping while in 4wd will cause the noise. this is a big issue to me because if i am coasting in
4wd with no load and come to a complete stop, say redlight on a straight road it grinds up front?? If their is no load and basically freespinning then why would braking cause the weird grinding?

Stop using 4x4 until you fix the problem. Crunching, clanking, and other strange noise are not normal. You can easily turn a simple and low cost repair into a complicated and expensive repair.

The part about no lube in the T-case would certainly focus your trouble shooting on the T-case and you might as well assume you have a stretched chain.

Your choice, stay in 2wd, fix the problem, or replace the T-case.