Rear Diff issue...anyone have any ideas?

[boscounderfoot]

Hello all, and happy holidays! I've got an '89 4Runner with Marlin built ARB equipped 5.29 diffs. I just got them in January, broke them in correctly, and changed fluid twice so far. I've only got about 2000 miles on them and they've been great. However, just this week, the rear began to feel like it has play in it. When I'm driving normally and ease off the gas, it feels like the ring and pinion are grabbing. If I lightly apply throttle, it feels almost like the pinion is alternating between the drive and coast side of the ring gear. The truck is turning 285/75x16's, stock 3vze, R150F & stock chain t-case. So no crazy set up. And I never beat this truck, ever.

My question is, since Marlin never answers the phone, I'm hoping that maybe one of you folks has an idea. Tomorrow, I'm going to pull the driveline and check the pinion nut and drain/investigate the fluid. If anyone else has any ideas, I'm all ears! Thanks in advance.

 

[txlonghorn85]

Is it possible the drive shaft got misaligned while you had it removed? My drive shaft symptoms mimic'd what you're reporting. Check your u-joints. Pinion angle changes with throttle application and is especially noticeable at higher speeds on the road when you apply/release the gas pedal.

 

[boscounderfoot]

You rule!!

Is it possible the drive shaft got misaligned while you had it removed? My drive shaft symptoms mimic'd what you're reporting. Check your u-joints. Pinion angle changes with throttle application and is especially noticeable at higher speeds on the road when you apply/release the gas pedal.

Yup!! Thanks brother, it was a bad joint. I didn't even need to disconnect the shaft to figure that one out. Shocking how quickly that problem reared its ugly head!

 

[boscounderfoot]

Days

I literally checked and lubed everything last fluid change. That was last month, and the truck only has ~250 miles of road use since then......oh well.