I have a 3.55 LSD 8.8" rear diff on my 2004 (04-08) Ford F150. Unbelievably the 10 bolts which hold the Ring Pinion in place have loosened (one having sheared off, one fallen out and a handful bent whilst still fully threaded)! I'm hoping the only serious damage that was sustained was a damaged diff cover and that everything will keep running. So, I've ordered some new bolts for the ring pinion, but need to know the torque values for these? Also, what should the toque be for the bolts holding the diff cover in place?

 

That axle is scrap. You need a rebuild if not a whole new setup.

 

What makes you say that? Care to expand a little please?

 

Once you have breakage like that everything is questionable. How long did it run like that? Was it worked on recently? How much noise and for how long? If it ran any time at all, the gears would be worn "funny". If it was worked on recently consider all work done to have been done wrong. If it was making noise and especially if it was doing so for any time, it's junk.

 

It ran like this for approx 6 miles (driving slowly, mind). I've owned the truck for 4 years, and the diff has never made any odd noises or given any trouble. Would you not even bother re-torquing new nuts and giving it a go?

 

So it was just worked on?]

 

Just looking at the chunks of metal missing from the parts I can see, I'm guessing that there are shrapnel spread throughout the casing. And to remove the remnants of those broken bolts from the ring gear, you will have to pull the differential, which means you're not that far from rebuilding the whole thing anyway. Why take the chance with re-using the old parts?

 

Not in the time I have ever owned it, no.

 

60 ft lbs according to this, Differential Installation Instructions | West Coast Differentials

 

It might be alright. I would tear it down, clean and deburr anywhere it got hit. Get it back together and slowly turn the yoke while putting some resistance on the ring gear, feeling for any resistance anywhere.