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Discussion Starter · #1 ·
I upgraded my rear diff cover to the AAM version with fins from the RAM 3500 and was wondering if the recommended fill amount has changed from the factory 3.17 quarts?

I do not fill the rear diff till it comes out the hole.
 

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Discussion Starter · #3 ·
The AAM upgraded "finned" diff cover I believe doesn't hold any additonal fluid from what I've read online.

Yet the RAM manual indicates a 3.75 quart fill and GM is 3.17 quart fill? RAM is a 4.10 rear end and GM is a 3.83. Not sure if this has anything to do with the fill level?

Some of these finned diff covers have a blue paint dot which is about 1/2" below the fill plug hole to indicate maximum fill level. Mine did not have this.

This is the one I have:
https://www.drivetrainamerica.com/7...-11-5-aluminum-finned-differential-cover-kit/
 

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The AAM upgraded "finned" diff cover I believe doesn't hold any additonal fluid from what I've read online.

Yet the RAM manual indicates a 3.75 quart fill and GM is 3.17 quart fill? RAM is a 4.10 rear end and GM is a 3.83. Not sure if this has anything to do with the fill level?

Some of these finned diff covers have a blue paint dot which is about 1/2" below the fill plug hole to indicate maximum fill level. Mine did not have this.

This is the one I have:
https://www.drivetrainamerica.com/7...-11-5-aluminum-finned-differential-cover-kit/


You need over 3 quarts, and less than 4 either way, so buy 4 and fill it up. Personally i have always filled it up to just below the hole, shove a little finger in there and bend it down and fill till it just touches your finger on level ground. Should be close to the 1/4 - 1/2" below the fill hole mark you are looking at. Since the outer hub bearings are lubes in gear oil that sloshes down the axle tubes, i would personally rather it be a little over than under, since the diff has a breather in it and your not going to blow seals out of it. Id rather sacrifice a little MPG and make sure those outer hubs are lubed.
 

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Discussion Starter · #5 ·
Makes sense now to me. I'll use something to verify if I'm near the 1/2" level below the fill hole.
 
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