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Rear Differential/axle fluid

February 04, 2011, 11:09:44 pm

Though I had the number of quarts that it holds, but can't find it.  Is 16 qts about right?

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Re: Rear Differential/axle fluid

Reply #1 – February 05, 2011, 11:28:29 am

Here's the info for our 93 225, Pat.
jor

REAR END
Rockwell RS 15-120
15 pints SAE 85-140
Ratio: 3.73

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Re: Rear Differential/axle fluid

Reply #2 – February 05, 2011, 04:56:19 pm

Thanks, I would have had ten times to much

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Re: Rear Differential/axle fluid

Reply #3 – February 07, 2011, 12:55:31 pm

I'm not too sure on the 15 pints. I bought a 5gallon pail of synthetic differential fluid and had a about one gallon left after I was finished changing it all out.

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Re: Rear Differential/axle fluid

Reply #4 – February 07, 2011, 01:34:36 pm

Note: On many of these Rockwell rear axles, there are TWO "full level" plugs.

The correct one is determined by installation angle of the rear axle.  Check with James Triana to see which of the two plugs should be used.  You do NOT want to overfill the axle.

Please let us know the answer and what axle you have.

Brett

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Re: Rear Differential/axle fluid

Reply #5 – February 07, 2011, 01:53:11 pm

Thanks Brett.  Will post what I find out.  I have three loose leaf folders full with manuals and info.  Thought I had all the info, but can't find it.  Want to get this done before Georgia trip in March.

Update - what I got back:
"Rockwell RS15-120 15 Pints.

Use Hypoid Gear Oil, GL-5, SAE 85w140 for ambient temperatures consistently between +10°F and up. For temperatures consistently below +10°F, consult your Rockwell, "Single Reduction Differential Carrier Manual".

Use the plug that is located at the center line axle housing. When the unit is full the oil will come out of the opening where the plug was removed.'

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Re: Rear Differential/axle fluid

Reply #6 – February 08, 2011, 10:03:04 am

Having a hard time locating the Hypoid Gear Oil 85w140 synthetic in containers less than the 5 gallon pail.  Can find Mobil 1 75W-140 synthetic in quarts which is okay.  But did not know if it was okay to substitute the different weight so I contacted Rockwell.  They said:    "You need to look out for one thing, the oil need to be of a GL5 consistency or greater.
If your oil is to this specification it will work."

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