1999 TJ trans noise

[Quarry Trash]

Hey all I recently acquired a 1999 tj, Titan engines 4.0l, ax15, np231, dana 30HP (4.10 gears and a lunchbox locker), Ford 8.8 (4.10 gears and a factory limited slip). The jeep runs great but I've been fixing little odds and ends since December. I have a strange noise coming from the trans that sounds like a bearing going out, it is noticeable when applying fue but its really bad when I let off the throttle and allow the engine to hold back on the trans. When I press in the clutch it goes away which leads me to believe its in the trans. I replaced the trans fluid with syncromesh in hopes it was the fluid but no such luck. The jeep has 22000 miles on the body so I'm assuming the same is true for the trans. My question is does anyone have the same problem? Thanks for any and all help.

 

[Ron]

throw out bearing?

 

[Quarry Trash]

throw out bearing?

Maybe so but I thought throwout bearing noise was obvious during neutral as well. This noise only happens while moving in gear.

 

[skyhighZJ]

Rear end. Check the yoke at the axle. See if there is any slop.

 

[Quarry Trash]

Rear end. Check the yoke at the axle. See if there is any slop.

Checked that and the setups are reasonably tight, not overly tight but decent. only a small amount of movement of the driveshaft before the axles begin to turn

 

[Yay!Gurrr]

is the 8.8 rear on leafs ?

 

[Quarry Trash]

is the 8.8 rear on leafs ?

No its a 4.5" long arm kit

 

[skyhighZJ]

Unjoint angles ? What’s the type of driveshaft. I guess my .02 is the rear axle based on info provided. Other thing could be tcase??

 

[shawn]

Checked that and the setups are reasonably tight, not overly tight but decent. only a small amount of movement of the driveshaft before the axles begin to turn

You're looking for side-to-side movement of the yoke in the differential, indicating that there's no preload on the bearings and the pinion is moving around in the housing.

 

[Black Bear]

You have a cv drive shaft? If so check the centering ball for excessive play

 

[Dawnpatrol]

You have a cv drive shaft? If so check the centering ball for excessive play

This. I had a noise that only occurred under load. When the clutch was pressed it went away. Turned out that the CV ball was about to go from not having grease.