Rear Differential Advice

[tmanzee]

Rear Differential Advice
So I was hearing some funny sounds coming from my rear diff on my 02 FX4 pulled the cover off and found 4 or so bolt heads have sheared off inside. This is way beyond my mechanical abilities to rebuild.

Have any ideas how this could happen beside me being a terrible truck owner and not changing the fluid enough?

What do you guys think:
Have my mechanic rebuild it?
Can anyone take a wild guess at how much that will cost just so I dont get ripped off.

Should I replace the whole axle?
What axles are compatible with my truck?

pictures here
https://drive.google.com/folderview?id=0B1N9QoJWFXaKaUw2S3h5TlhubzQ&usp=drive_web

This is a torson limited slip

 

[BRUTUS_T_HOG]

Can't say I've ever seen that unless those bolts were not torqued correctly or didn't use thread locker.

If the case and gears are not damaged I'd have your mechanic replace all the bolts and torque them to spec. Also using tread locker

 

[Mac]

If they are sheared off, that's not from loctiting or proper torque. Maybe over torqued would do it. There was a recall on those or similar rear ends but no idea of what the problem was. Replacement for a torsen like yours gets expensive, cheaper alternative.
Dave