ledangel

Hello, I just bought a '98 xj sport automatic trans 4.0 a month ago and today when i went to reverse it didnt want to move and felt as if the tranny was engaging and disengaging. There was also a bit of a clunking noise. When in neutral the jeep will not move, well i cannot push it by hand anyway.
ALSO....after driving in 4WH when i switch into 2w it will make a loud thump at about 25-30 mph. I have a minor leak in the rear differential and refilled that about 2 weeks ago just to be sure it wasnt dry, it only took about a pint so i dont think that is an issue. The transfer case also whines when reversing. After driving for 2 miles at 35 mph the problem kinda when away, it still hesitates to go into reverse and when it does it goes in hard and I have to give it a bit of gas to get it to engage.
Any and all help would be greatly appreciated.

Also I have been reading over this forum since i got my XJ and you guys have helped me quite a bit with some other minor issues so i must thank you.

**EDIT**
I played around with it a bit more and found that it will roll forward in neutral fine but when it rolls backwards there is a grinding sound coming from either the front dif or the TC. It doesnt want to move at all in low 1-2 and it feels like the parking brake is on in drive and low 3. I can hear the rear dif click in when shifting in and out of gears (neutral to drive, park to reverse etc.) So i dont think its the tranny. I checked the fluid in the front dif and its full and clean. Also checked the fluid in the rear dif which is full but not as clean as the front, i would assume that this is because 2WD is used more than 4WD.
I found that it has the 272 TC, not sure that will help any.

MasterShakeXJ

change the fluid in your diffs and check to see if you have fluid in your tranny. check ujoints and driveshafts. it might be good to also change the fluid in your tcase and check the linkage.

also might want to check your brakes to see if they're frozen or warped. just a thought.

ledangel

Trans fluid is full, I thought it may be the tranny but i can hear and feel it clicking in in the rear diff, its doing the slipping in drive now too. Its odd be cause it seems like it goes into gear but then when i give it gas it doesnt move at first then it will "jump" into gear.
I assume i need a special tool to check the TC fluid? Not sure i have seen a hex that large in any kits.

TY For your help btw.

mike37

what you are describing sounds like
low fluid in the tranny

you say its full

not trying to insult but
did you check it right

engine running at normal operating temp tranny in park on level ground

mike37

to check the TC fluid just remove the big plug on the back
about 2/3 the way up on the driver side of the drive shaft

the fluid should be at the bottom of the hole
if its not add tell it wants to run out it is AT fluid

ledangel

Yeah i thought low fluid too...not the case...on the dipstick it says check it neutral doubt it matters...it actually seems like it may bit a bit overfull but not sure going to check it again in a few mins.
The Fluid level in the tranny wouldnt make the TC or front diff though...thats where i am lost..I am thinking maybe the fork thingy...hehe..in the TC is bad/bent? or Maybe a gear has sheared in the Front diff?
The fact that it grinds in reverse makes me think its the front diff. But it is hard to hear exactly where its coming from without someone else to sit in the jeep while i roll it back.
I know quite a bit about autos, just not much about 4WD.

The plug for the TC what size is that on a 272?

ledangel

Sorry about all my typos I have been up for nearly 48 hours. lol.

mike37

not sure the size
but its in the red circle

winston427

What is your mileage? If the PO neglected the maintenance, then you should probably do a trans filter change as well. A dirty filter will block the flow of fluid and cause slipping.

mike37

this is better

ledangel

Yours is slightly different than mine. The plugs on mine are hex or allan bolts, look to be maybe 3/8 in. Wait...I think i may have a few of them from doing a brake job a while back.

ledangel

Mileage is 94500.
The slipping isnt what concerns me as much as the grinding and the fact that it is very hard to roll in reverse. But you are right....I am in the process of changing all the filters and fluids. Bastards at valvoline put 5w30 oil when my wife took it there so i am going to have to drain that and refill with 10/40..
I also plan on rebuilding both diff covers and rebuild where needed.

mike37

remove the front drive shaft to eliminate any front axle problems

winston427

Block the front wheels, place the rear on jack stands, put it in neutral and rotate the tires by hand. Listen for odd noise in the driveline. Then start it, put it in reverse and let the wheels turn while idling. That may help pinpoint the issue.

ledangel

Yeah I am thinking about doing that just to diagnose the problem. Winter seems to be over for the most part anyway.
I just checked the tranny fluid level again and it is still reading high so I am going to have to drain some..I will never take another vehicle to a big chain oil change place again.