Did an oil change on the rear diff of my LN46 and out came a big blob of liquefied metal and chips. Can't be good! What could be causing this anyone?

 

How much play do you have in the diff?

 

If it makes no noise and has very little play...don't stress it. The differentials on these trucks seem pretty tough.

 

Yeah, there is a bit of play there. About 5mm. I do get some driveline noise especially when i'm at speed and take my foot off the gas going down hill....

 

Well, you can always start looking for a used rear diff. Not sure what your level of experience is with working on these trucks, but it's not a very hard job to swap a new one in.

I actually got one just for the price of shipping. A lot of people around here have put lower gears in their trucks, so they may have a spare with stock gears laying around, taking up space in their garage...

Do you know what gears you have? What exactly is your truck? Year and model and all that. It actually should say somewhere on your engine compartment tag what gears you have.

 

Factory gears are 4.88's for LN46.(which is a 4 Door 1st Gen).

 

Thanks trekker. I'll start looking around for one (or two...) i'd like to get a lower gear ratio for road driving given that its a 4cyl 4 speed.

 

Ha I just checked the photo thread...yeah you've got a different model than we're used to over here!

If you look around at whatever classifieds you guys have over there, or junkyards, or offroad groups, whatever. Somebody probably has one in better shape than yours.

All it takes is dropping the rear drive shaft, unbolting the rear brake lines from the wheel cylinders, a couple bolts on the brake drums, slide out the axles, unbolt the rear diff and slide it out, clean it all up, put some sealant on there, put the new one in and put it all back together.

I'm really no mechanic, and it was an afternoon job for me, with no help.