Changing the Rear Differential Oil

skywarn · **Posted:** Wed Jul 18, 2007 11:24 pm

It's time to face facts. Every once in a while your rear end needs a little help. Whether you drive a rear-, front-, or all-wheel-drive vehicle, the wheels spin by way of a differential. The gears inside the differential distribute engine energy to the axles and the axles spin the wheels the right way at the right speed when you hit the gas.

Another important function of the differential is to allow the drive wheels to spin at different rates as you round a corner. The inside wheel spins slower than the outside wheel as it travels a shorter distance around the bend. From this difference, the differential gets its name. The gears inside the differential slide around coated in a slippery film of oil. Just like engine oil, the differential oil must be changed at regular intervals. Not quite as often, but at regular intervals nonetheless. Without the lubricating properties of this high-pressure gear oil, friction will quickly wear through the special layer of hardened steel on the gear teeth, and the gears can fail prematurely.

You will need 3 quarts (4.4 pints) of 75W-140 Synthetic gear oil. You could use RTV however to save a lot of trouble use a gasket. You can order a gasket from www.lubelocker.com and order the Chrysler 8.25 gasket

DarbyWalters · **Posted:** Thu Jul 19, 2007 11:55 am

Be sure to see if you require an additive if you have a LSD/Trac-Loc rear end. Always check your owners manual for factory specs.

0311_DoC · **Posted:** Fri Oct 12, 2007 11:26 pm

skywarn wrote:

It's time to face facts. Every once in a while your rear end needs a little help. Whether you drive a rear-, front-, or all-wheel-drive vehicle, the wheels spin by way of a differential. The gears inside the differential distribute engine energy to the axles and the axles spin the wheels the right way at the right speed when you hit the gas.

Another important function of the differential is to allow the drive wheels to spin at different rates as you round a corner. The inside wheel spins slower than the outside wheel as it travels a shorter distance around the bend. From this difference, the differential gets its name. The gears inside the differential slide around coated in a slippery film of oil. Just like engine oil, the differential oil must be changed at regular intervals. Not quite as often, but at regular intervals nonetheless. Without the lubricating properties of this high-pressure gear oil, friction will quickly wear through the special layer of hardened steel on the gear teeth, and the gears can fail prematurely.

You will need 3 quarts (4.4 pints) of 75W-140 Synthetic gear oil. You could use RTV however to save a lot of trouble use a gasket. You can order a gasket from www.lubelocker.com and order the Chrysler 8.25 gasket

so what is the pro/cons versus gasket and RTV ?

0311_DoC · **Posted:** Mon Oct 22, 2007 1:37 am

nobody??????

Jeger · **Posted:** Mon Oct 22, 2007 9:03 am

Lubelocker Gasket....simple, no wait, hard to mess up.. maybe a bit pricey but reasonable.

RTV.....Uhm...cheaper.... works fine, but you can screw it up.

valkraider · **Posted:** Tue Nov 13, 2007 8:36 pm

Once I changed it once and knew I had good high quality stuff in there, I just use a hand pump to pump it out. I get about 97% of it out without much fuss - and then I don't need to replace the gasket.

I get probably another 1% out by working with the hose...

But I wanted to make sure I had good high quality so that the 2% that stays in is fairly decent...

Probably every three or so I would want to drop it and do a complete change. But getting 98% with high quality lube should be good enough for three changes in a row...

Goglio704 · **Posted:** Tue Nov 13, 2007 9:46 pm

I just take the plug out. :wink:

click for larger view...

Endurance · **Posted:** Tue Nov 13, 2007 11:06 pm

Goglio704 wrote:

I just take the plug out. :wink:

click for larger view...

Dude that is awesome!

0311_DoC · **Posted:** Wed Nov 14, 2007 12:08 am

Goglio704 wrote:

I just take the plug out. :wink:

click for larger view...

ok so did you just drill a hole and then get a bolt and washer ???

Goglio704 · **Posted:** Wed Nov 14, 2007 1:21 am

Drilled in 3 or 4 stages starting at 3/16" and working up.
Tapped to 1/2" 20.
Installed 1/2" magnetic drain plug with copper sealing washer.

immadmacs · **Posted:** Thu Jan 10, 2008 9:31 am

The drain plug is great. I was looking at getting a cover with a plug from Ruff Stuff http://www.ruffstuffspecialties.com/cat ... p-152.html but if I can tap my the differential without spending the 115.00 then I will. Did you take the cover off when you drilled it to clean the shavings?

Goglio704 · **Posted:** Thu Jan 10, 2008 10:07 pm

Yes, the cover was removed. Let me caution you also, if you don't get this drilled and tapped straight, you will likely wind up pulling your rear axle and carrying it to a machine shop to fix the uh oh. I have friends who would have helped me had mine gone wrong. My point is that $115 for a cover could be a bargain. Bear in mind too that I still have a paper thin cover instead of the nice heavy plate. If you wheel hard, you might be better off with the cover.

tonycrd · **Posted:** Thu Jan 31, 2008 1:42 pm

Don't mean to be a smart *ss but this cover won't do you any good. If you fit it so the plug faces down how are you gonna fill the diff? Through the breather hole?

Just a thought: take of the original cover. Drill a hole in the lower part. Weld a big nut on it. Or in it if there's enough room.

Fit a drain plug. Done.

crd liberty · **Posted:** Thu Jan 31, 2008 4:05 pm

http://www.barnes4wd.com/chrysler-diffe ... -2177.html

How about this one?

crd liberty · **Posted:** Thu Jan 31, 2008 5:01 pm

Here it is pictured.
Any good ????????????
Steve

crd liberty · **Posted:** Fri Feb 01, 2008 8:20 am

tonycrd

The one you pictured above is available with the drain plug
for 5 bucks more. Saw it on Ebay. Rough stuff makes it.
Steve

immadmacs · **Posted:** Fri Feb 01, 2008 12:45 pm

Look under extras for the 5.00 drain plug option. And you don't sound like a "smart" *ss to me. -------------------Just joking with you.

immadmacs · **Posted:** Sat Feb 02, 2008 10:51 pm

I changed the fluid today. I found a gasket at Auto Zone for three dollars and change. It has ROL Gaskets printed on the package. FP- RDS55047.

honey_don't · **Posted:** Fri Feb 29, 2008 5:07 pm

instructions from the package for reference:

darinb · **Posted:** Mon Mar 15, 2010 4:18 pm

I know this is a rookie question.. but how do you refill the diff? Is that rubber thing I see a fill plug?

If so.. the procedure is?: remove the cover to drain the fluid.. then reinstall.. then remove the rubber plug and fill?

Changing the Rear Differential Oil

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