pulled my rear differential found this
 

pulled the cover to drain out the oil didn't find any metal shavings or missing teeth that i could see someone said it might be the pinion hitting the metal but i dont see how it could.

any ideas? :argh: ive never herd of anyone having this problem before. i bought this truck used so i have no idea what happened it runs fine but i just want to make sure its nothing serious. i changed the oil a day or two ago . haven't changed the pinion yet but i had to drain the oil because it was over due

What the hell? :s:

looks like at one time the pinion nut may have backed off and allowed the pinion to contact the carrier. check the pinion nut and make sure it is torqued properly and has the proper amount of backlash and you should be OK.

this could also be from a previous issue that was fixed but they used the same carrier but different ring and pinion.

It uses a crush washer/cone, so if its loose it will need to be rebuilt.

yeah i had no idea what caused it when i first looked at it. nothing seemed lose when i worked on it but im going to pull the pinion sometime this week, im hoping it may have been fixed in the past. the one thing that i noticed when i took the cover off it still had the tags on from ford witch makes me believe something had been repaired on the rear end it was a northern truck so it would have some rust on it if it was original to the truck. heres hoping.. ive never seen anything like this before

if you take the pinion nut off or remove the pinion, replace the crush washer that CSIPSD mentioned, this is a must as they are not re-usable.

okay ill make sure to replace it.

found out the pinnion is smashed yolk is warn out and the bearings are shot there goes a chunk of money :argh:

Might be cheaper to just swap in a new axle... Just FYI... They are SO common (every superduty from 1999 to 2008 use the exact same Sterling 10.5...) that wrecking yards sell them for $400-$700 bucks.

all the local scrap yards dont have any and i found one but it was bent and crushed and if i get a used one ill run into this again down the road so i guess im better off geting it all replaced the rear gear is good just everything else is shot