Differential Lube

[mattluttrell]

I see 5F in the winter and 100F+ in the summer. I always just put 75Wor80W-90W. I put the same stuff in the BMW, Escalade or Jeep with air locker and limited slip.
I've never had worn gears or bearings or oil go bad other than from being submerged in a river.

I'll pull carriers and gears on a car once a year so I'd see the damage. I've been lucky with the default gear oils I guess

 

[MarkD51]

there was a time when a synthetic would eat up a specific rtv so it was not advised in the rear end unless it was manufactured after a certain VIN breakpoints. There was a number of different axles involved but the the but the 1/2 rears in our suv were clear of any breakpoints from the factory. Besides chemical formulations have improved over time. you can chose between two different gasket types for the rear if you like. the more expensive one is preformed like the valve covers, improved intake design and the oil pan. that one would require no extra sealant of any kind. the 75w-140 was initially recommended for the front axle when people had axle shifting issues when really cold outside but is permitted in front or back for consumer choice.With our GVWR specs 75w-140 synthetic gl-5 compliant is more then enough.

I did ultimately decide to just go again with Mobil 1 75-90W, got 3 qts, a Felpro Gasket, small tube of Permatex Ultra Black Sealant, and a can of VHT Satin Black Engine Spray Paint. Will do the lube changeout hopefully this weekend if weather cooperates here.

My plans are to drive the truck a few miles, warm up, then drop.

I have read some here, about fill capacities, and how some fill to the side fill port, and others suggest not to, to fill slightly below this point. I've always filled till the Lube just began to flow out the Port, and capped? Any harm in this?

Vehicle is my 1997 Tahoe 4x4. (Rear Differential)

I plan on cleaning-prepping all mating surfaces, they'll probably lastly get a 91% alcohol wipe, and thought of just wiping a very thin coat of the Permatex evenly on both sides of the Gasket. button up, torque to 30 ft lbs (in 1/3rds approaching final torque values) and of course in a criss-cross fashion.

Let Sealant set up overnight, then fil the next day.

Sound OK?

 

[SunlitComet]

continue to do that voodoo that you do so well.

 

[mattluttrell]

I think the general idea is to get good oil on the metal surfaces. I think all the other decisions have little impact. I think your plan is good if not over the top. I'd just fill until it starts coming out and don't tighten the bolts so much that it warps the cover. It should be great.

 

[MarkD51]

continue to do that voodoo that you do so well.

That sounds like a go, and a thumbs up from you.

I'm going to sleep better tonight. Thank you SLC!
Mark

---------- Post added at 07:50 PM ---------- Previous post was at 07:37 PM ----------

I think the general idea is to get good oil on the metal surfaces. I think all the other decisions have little impact. I think your plan is good if not over the top. I'd just fill until it starts coming out and don't tighten the bolts so much that it warps the cover. It should be great.

Smartly, many years ago, when I worked for Amtrak as a Carman-Mechanic, I amassed an expenisve array-quantity of Snap On Tools. Some regrets later, as I probably could've bought twice as many Craftsman Tools! Got a few good Torque Wrenches though in the process, and my hands over the years have "a built in torque wrench."

Ahh, hindsight always has 20/20 vision, doesn't it?

A good plan I found, is to torque in 1/3rds, reaching required final torque values.

For sure, I'll eyeball the rear cover after removal, inspect, and finesse any weird dimpled bolt holes for trueness.

I'm hopefully going to enjoy doing this job, which I'm sure all will go well, love working on my Hoe, keeping it up, and looking-running good!
Thanks for the reply, and have a great weekend folks!
Mark

 

[SunlitComet]

Long live snap-on.

 

[MarkD51]

Dropped Rear End Cover this morning, lube looked fairly nasty, and the internal magnet had some "furr" around it, but no shavings, or anything large, so reckon that was a good sign, and that furr on the magnet of course can be expected. Cover came off easy, no wrestling.

All seemed to go smooth, took a wire brush attachment, and a drill, and cleaned up the outside of cover, cleaned, and got all mating surfaces clean.

All torqued up, but will wait till tomorrow, or maybe even Monday to fill. No rush, I figure the longer the Black Permatex Ultra sealant sets up and cures, the better.
Mark