Trans slipping?

Hi Guys,
88 XJ 4.0 auto Im hearing a clicking sound from either the trans or possibly rear diff when backing up hill or backing on the flat during hard acceleration. backing down hill or under normal acceleration. Which is more likely? trans fliud level is goor have not checked rear diff yet. If you think its the trans any recomondations for a good shop for trans work in San Jose Calif.

plus which tran is it? how do I tell?
thanks for any info

Put it in 4X part time and turn a corner slowly, if it gets significantly worse, it could be a front U-joint. Possible it could be a driveshaft U-joint. I've also heard that clicking, when a spring broke in the rear drum (also often makes a whoosh whoosh whoosh sound and sometimes clicks).
If it doesn't click sitting still, it´s probably not torque converter bolts. A loud roar in reverse, is often the first sign of loose/worn bearings in the rear differential.
How loud is the click? Does your speedometer jerk around some? I've heard the speedo cable click, when the lube is dried out.
Darned sounds are hard to chase down and it gets really expensive, letting a mechanic hunt them down by the hour.
The tranny is an AW4.
Also possible you have a chipped or worn tooth in the rear diff. the spider gears are kind of failure prone.

was not trans was my steel breaded break lines being pinched between my tire and the wheel well