Changing diff fluids...what do I need?

[Tiffster]

Well per Satans advice I am going to change the gear fluids at 250 AND 500 miles. Well 250 change is this weekend and I need to know what I need to do this. Have the RTV sealant, know I need more cheapy gear oil....but what else? Something about brake cleaner keeps popping into my head, but not sure why.

Also, at what point should I switch to synthetic oil in the diffs?

[satan]

OK, That's about right... just drain (really drain!) then wipe out,
close, and fill.

The brake cleaner isn't all that necessary, but if you've got it, a
little brake cleaner will help to get the stuff off of the inside of
the cover.

The advantage of the 250mile change is just cheap insurance -- you
get a chance to get out any lube that has broken down, and look over
everything - less metal and better lube for the next 250 miles!.
Cheapo stuff of the right grade is good for the first change.

You can go to synthetics at the 500 mile change if things are clean
and happy -- then get into the "normal" cycle -- annually, and
after every axle-under water crossing. ANAL I know, cheap insurance
and great cologne -- really gets the chicks!

The additive that JJ's talking about is a BG product. They changed
the name, used to be EPC (Extreme Pressure Concentrate); now called
MGC (Multi-Gear Concentrate)... Good friction modifier with
dispersant properties to keep any metal in suspension so it's easier
to get out of the damn diff....

[bigfodee]

what color sealant do you have? I would definately reccomend the Ultra Black. I use the brake parts cleaner to clean the inside of the diff cover and the gears. The cleaner will dry on the gears in about 10 seconds, but its possible to build up inside the diff cover. Which is actually what I like because I can get a rag wet with it and clean everything well.

I dont know about this 250 mile deal. I use synthetic and change it every month, unless I go 4 wheelin. My gears have got 150,000 miles on them and they're fine.