I have a Dana 70 from a later Ford truck ('80's?) under my '65 F-350. It's got 4.88 gears which are rather short for highway driving even with the 0.85 OD in the brownie I added. 20+ years ago I also bought a used 4.11 open diff (4 spider gears). It's been sitting since then and is very gunky with some surface rust.

Gears are now off, cleaned and soaked in Evaporust, and look like they'll work. Even if they're a bit noisy I won't hear much from out back anyway and I don't even put 1000 miles a year on it The previously frozen pinion bearing even turns smoothly now, although of course I am going to put all new bearings in!

What about the differential itself? How do I degrease it before Evaporust... my thought is to soak it in a 5-gal bucket with Simple Green or a similar cleaner. Will this hurt anything?

Any tips I should be aware of when completely disassembling the diff itself (taking out the bolts and separately cleaning the carrier, cross shafts and spider gears)? Thanks!

 

Depends on how fussy you are, and how much (or how little) you're willing to spend
If there are any local shops that rebuild LARGE engines (semi engines, Cat engines, etc), they will likely have a jumbo size "Jet Wash" for cleaning and degreasing the big engine blocks. These units have a heater in the bottom that contains a degreasing solution (caustic), which is heated, then pumped through numerous nozzles that then spray the object inside while it's being rotated inside the cabinet. Your housing will come out clean enough to eat off of (after a rinse But, as you can imagine from the description, this will not be free.
I've done the cleanup on several 9" housings over the years, just a a couple cans of degreaser, and a pressure washer, turned out OK. One thing to be very careful of after you've sandblasted the housing (**blasting to be done ONLY after a thorough degreasing, as any remaining gunk will trap sand), is to take a blowgun, and be sure to thoroughly blow out all the internal nooks and crannies, as any sand you miss will most certainly not be healthy for gears and bearings........

Here's what the Jet Wash Cabinets look like.....
https://www.bendpak.ca/shop-equipmen...hers/rs-750ds/

HTH
James

 

I cleaned up my Dana 44 housing by first scraping it. What didn't easily scrape off, I warmed up with a propane torch. The hardest gunk then came off with scrapers or wire brushes. Final cleanup was with a degreaser.

 

Thanks, but I was not asking about the housing. There's a million threads to read all over the net.
I meant, cleaning the differential itself. That consists of a carrier, spider gears, cross shafts...