Rear axle service.

[Cummins12V98]

The severe gear normally doesn’t need a modifier, but occasionally it does.



The new 12.0, HO axle, wants 75w-140 for DRW.

Interesting. Going back to the Dana days.

 

[bcbender]

OK... Fresh eyes this am,

Did not drive the truck but have a few questions because I want to confirm 100%... Which AAM axle is under the 20' 3500 HO? It sure looks bigger than my 11.5 I had in my 05, is it the 11.8? I assume the AMZOIL Severe Gear 75W90 is fine, but as I said last night I had 8 qts and i am down to less than 1/2 left, seems the front too a little about 2.5~ 2.75Q and the rear took all of 4.5Q (it is hard to judge with swapping bottles and the hand pump....) I was going to go back home this afternoon and pull the fill plugs to make sure they are happy, (I filled & drained on the lift using Ron's method of lifting one side / then the other for an hour). I am glad I had enough oil on hand as it was left over from the 04 and would've been just right with my MAG HYTEC cover so just don't need to introduce any problems..

 

[AH64ID]

You have the 12.0” axle with the HO.

The SO (SRW/DRW) uses the same housing but has the 11.5” R&P.

Yes 75w-90 is fine. The only configuration that calls for 75w-140 is the HO DRW.

 

[bcbender]

You have the 12.0” axle with the HO.

Ok.. that makes me feel better, especially since I passed 3.5 Qt of fill and was not near the level line.. Should I squirt some friction modifier in it or just let it ride in your opinion? Its sitting at my shop right now, I was told that with the friction clutches I should go down and drive a few times in circles to get the new lube oil on all the plates....

 

[AH64ID]

I would wait and see if it chatters. The SVG has some modifier in it already.

If it does chatter I’d use the Amsoil friction modifier.

 

[Signal73]

Just an FYI on 19+ trucks, “To the fill plug” is over full.

 

[Cummins12V98]

"Just an FYI on 19+ trucks, “To the fill plug” is over full."

They all say something like that. Fill till it runs out and slap the plug in!!!

My Sons GF's 2021 2500 held about 4.5 quarts but my 15 HO DRW only holds 4 quarts. Must be I have a bigger gears making less room for fluid. My friends 13 DRW only took 4 quarts also.

 

[AH64ID]

Just an FYI on 19+ trucks, “To the fill plug” is over full.

View attachment 130950

Interesting. I’m guessing it has to do with pinion angle on the coil springs as the 2500 and 3500 SO SRW have the same axle.

The 3500 is the still okay pouring out the hole, like AAM has been since 03.

 

[AH64ID]

My Sons GF's 2021 2500 held about 4.5 quarts but my 15 HO DRW only holds 4 quarts. Must be I have a bigger gears making less room for fluid. My friends 13 DRW only took 4 quarts also.

Different axle housing 19+

 

[bcbender]

My Sons GF's 2021 2500 held about 4.5 quarts but my 15 HO DRW only holds 4 quarts.

Yeah, My 04 didn't hold that much either, glad I had a couple extra quarts of Sever Gear laying around since both axles took about 1/2 quart more than my previous truck did... I think I am not going to worry about the front axle "not being" 1/4" below, nothing even turning in there except the side gears..,, Leave it to AAM to change a long standing common procedure for transmissions and axles and replace it with a "coat hanger" needed.. I assume it wont leak due to the fill level being slightly higher... or should I waste my time drawing some out..

EDIT: any downside of leaving it "level" with the hole?

Different axle housing 19+

That was why I was asking about the fluid capacity, I did not know about the 12" but knew it looked bigger than the 11.5" I had previously

 

[bcbender]

I think I answered my own question

So yes... level with the fill plug hole on all but the rear axle on a 2500 is <IN SPEC>

 

[kthaxton]

My 2500 has an etching on the diff cover that says "fill level" (or similar), it is about 3/4" below the fill plug.

 

[NIsaacs]

EDIT: any downside of leaving it "level" with the hole?

None at all. If you read the fine print that is what Ram is saying. 1/4" + or- is just that. Minus 1/4" is that much below the plug. Plus 1/4" is full....

 

[BigPapa]

1/4"-1/2" below the fill hole is pretty standard. I have seen several trucks in the shop brought in for pinion seal leaks. We would pull the plug and find the fluid level at the hole or fluid running out. We'd pull some out until it was at the proper level below the hole, clean the diff off, and send them on their way. I don't recall any of them coming back due to a pinion seal leak.

 

[Cummins12V98]

Different axle housing 19+

Man this is too much to keep up with!!!

 

[Cummins12V98]

I think I answered my own question

So yes... level with the fill plug hole on all but the rear axle on a 2500 is <IN SPEC>

View attachment 130951

So it can be 1/2" below to even with fill hole and be "JUST FINE"

 

[Cummins12V98]

None at all. If you read the fine print that is what Ram is saying. 1/4" + or- is just that. Minus 1/4" is that much below the plug. Plus 1/4" is full....

Great minds think alike!

 

[bcbender]

Made this today.... (based on the FSM excerpt about using a coat hanger or Zip-Tie)... Interesting, I put her down (off the lift) and after sitting, both axles were ~ 1/4" below the fill hole........... so perfect!

So based on my "checking and confirmation study", I think I will start selling them... $2.49.. , but wait.... I'll send ya a second one free!!!! (just pay separate shipping and handling)..

 

[bcbender]

Those that dont have a lift to get the "proper prefill" will need this tool...

 

[Cummins12V98]

Great idea but spec is good letting it run out the hole.

I have done something similar to get the fluid at the proper level on Motorcycle shocks.