How often should this be done? 30? 50k? I will be towing about 8500lb and think I should do this before I start camping this year. Traditional or synthetic such as 75w-140? My cover has some rust issues, I think I read on here that the 08 cover fits the rear diff. Is that right ? Thanks

Joe

 

The newer rear cover does fit but you will need slightly longer bolts. It's on my list as mine has rust issues as well! The short term fix was to sand it down last week when I changed my fluid and painted it black again. I'm running Royal Purple Max Gear 75w140 in mine - has the limited slip additive already in it. The last time I did mine was 30k ago with Amsoil and haven't had the axle in water but it was a murky brownish color which indicates it is time for a change. Clean the mating surfaces well and use a good bead of sealant since there is no gasket. Every 30k or so is typically when I change mine using synthetic - cheap insurance and it gives you a good opportunity to see if there is any issues. Don't forget the front diff and the transfer case if you have 4x4 - 75w90 in the axle and Mercon V in the transfer case.

 

I just did mine for the first time since I don't care to say when. I slapped one of these on too: Riffraff Diesel: Riffraff Diesel Rear Diff Cover

Really happy with it since it has a magnetic drain plug and a fill plug. Plus the O-ring seal makes it a lot less messy to install.

You V10 guys could just paint over the "Diesel" part.

 

I forgot on my cell phone mh sig does not shoe up. 01 7.3 2wd. How much fluid does it take for rear. I would dare to say mine never has been changed.

 

For what it's worth, a 2008-up aluminum cover works great. You just need longer bolts, 5/16" x 1 1/4" IIRC.

Get 4 quarts of 75-140 synthetic oil.

 

Great, I will order one from a vendor. You can get the oil at NAPA or somewhere right?

 

Most auto parts places will carry it. Just make sure its 75-140 synthetic.

 

Yep, NAPA, Oreilly, even Walmart carries 75-140 around here.