I checked the fill plug on my 99SD F250 10.5 limited slip axle. Lots of metal shavings. Once I removed the pan I can see the pinion gear has been touching the carrier. What would cause this and how does one repair a problem like this?

 

I doubt it was the big pinion bearing. Although it is probably junk as well by now. It was probably whatever sets it's bearing preload something has broke or the nut backed off. I don't know off hand if it uses a crush sleeve to set preload of it's shimmed. Just have to tear it down and see for sure what happened.

 

I am not much of a shade tree mechanic. But I can move the pinion side to side/up and down with just one hand on the drive line. One small mom and pa shop quoted me at 500 for labor replace the pinion bearing/seal and carrier bearings. Then I also found a used axle with close to 200K miles for $360 dollars but 200 miles away. Then another wrecking yard has a 88K miles axle for $600 delivered 20 miles away with core and shipping charge. I am leaning to buying the used one. Ford and Sterling put so many different codes on their axles it is enough to make your head spin. The truck has the same C1 on the door jamb but not quite the matching axle code s409c on the axle tag. I would really like to take a peek inside the pumpkin before purchase though. I am reading now that many of these 10.5 sterling axle near 200K miles the pinion bearing is done. I just don't want to buy a used axle and have to replace the pinion bearing and seal as soon as I start using it.

 

It's a crush sleeve in the 10.5's. It could be a few things as you said. maybe a pinion shim came apart.

Had this diff ever had any work done to it before?

 

I am leaning on just replacing the whole axle with a used one.
If I was to get a used rear axle up to what year would work?
TIA
Matt

 

Bad bearings or a loose nut.