first diff fluid change after gear install

recently had 4.88s (usa standard) installed in my d44 in my comanche. its been ~300 miles and its time to change the fluid. i noticed the fluid was a brownish color and had a decent amount of metal flake in it. also, on the ring gear, there is what looks like little specks on the edge of the tooth like its dirty, but i cant feel them. all this sound normal? i had a shop do the install so it should be set up right. ill get a pic up soon. going to be throwing on a ruffstuff diff cover after i paint it.

Metal flakes aren't good, maybe they are leftovers from your last gear set, the mechanic failed to flush out before the new install. It may also be a bearing with too much preload slowly self destructing.

When I''m inspecting a ring gear I look for black or blue spots (splotches) on the mating (shinny) surface. Usually means they got too hot.

Look for any play in the pinion, grab the pinion yoke and shake it up and down, I kind of slap it with the palm of my hand. Pry up on the ring gear with a pry bar and check for play in the carrier bearings.

I'm by no means a gear expert, but all of my attempts were successes.

This was ~80 miles on a fresh gear install. I had to change a bad axle seal, so I pulled it apart.



The first 500 miles is going to be the most dirty. The gears are seating into the pattern. As long as there aren't any noticeably large pieces, I'd say you're fine. Shavings and flakes are normal from what I've seen. I put some magnets on my RuffStuff covers, and was amazed at the particles collected during the break in process.

I've always had metal shavings after the first few hundred miles. If there was something terribly wrong, I would think you would hear and/or feel it. Change the fluid again at 1K miles. Even then you will probably see some shavings. Not sure about the specks on the tooth though.