3500 HO 12"AAM Capacity

[ah.asher2]

I'm sorry if this has been answered before, I just couldn't find the answer anywhere. Does anyone know what the capacity of the 12" AAM Rear Axle? Im approaching my "break in" oil change and I want to make sure I have enough before I pop the cover off. Side note, has anyone used the Hot Shot Secret Gear Oil, specifically 85W-140? I use all of their other products, but I see most reviews about Amsoil Severe Gear.

Thanks!

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[H3LZSN1P3R]

Did you check your owners manual its usually there under maint section

 

[John Jensen]

Did you check your owners manual its usually there under maint section

The Owner Manual does not give differential oil capacities, only product & weight.
Same with the transfer case

 

[ah.asher2]

The Owner Manual does not give differential oil capacities, only product & weight.
Same with the transfer case

Yeah, I was in the process of double checking I didn't miss it somewhere.

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[Zrojas]

I'm sorry if this has been answered before, I just couldn't find the answer anywhere. Does anyone know what the capacity of the 12" AAM Rear Axle? Im approaching my "break in" oil change and I want to make sure I have enough before I pop the cover off. Side note, has anyone used the Hot Shot Secret Gear Oil, specifically 85W-140? I use all of their other products, but I see most reviews about Amsoil Severe Gear.

Thanks!

Sent from my SM-G988U using Tapatalk

First the oil specified for the 12" rear end is Synthetic 75W-140 (MS-8985). Limited slip additive is required.

The factory service manual lists two 12" axles and capacities:

305 AA (12.0)(Anti-Spin) - 8.79 pints
305 AA Banjo (12.0)(Anti-Spin) - 12.7 pints

Oil type for both is the same.

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[John Jensen]

First the oil specified for the 12" rear end is Synthetic 75W-140 (MS-8985). Limited slip additive is required.

The factory service manual lists two 12" axles and capacities:

305 AA (12.0)(Anti-Spin) - 8.79 pints
305 AA Banjo (12.0)(Anti-Spin) - 12.7 pints

Oil type for both is the same.

Sent from my SM-G975U using Tapatalk

Good info

Your data says
First the oil specified for the 12" rear end is Synthetic 75W-140 (MS-8985)
I realize the manuals are notorious for being wrong. My 2020 3500 HO manual says:
We recommend you use SAE 75W-85 HD Ram GL-5 Synthetic Axle
Lubricant in 9.25 Front, 11.5 and 12.0 (Single Rear Wheel) Rear Axles.
and
Use Mopar GL-5 Synthetic Gear Lubricant SAE 75W-140 in
12.0 (Dual Rear Wheel) Rear axles. Limited slip additive is required
for limited slip axles.

Your data says
305 AA (12.0)(Anti-Spin) - 8.79 pints
305 AA Banjo (12.0)(Anti-Spin) - 12.7 pints
What axle do I have?

Your thoughts?

 

[Brutal_HO]

Looks like "Banjo" is the airbrake HD version.

 

[Zrojas]

I see that the 2020 and 2021 Ram Owners manuals specify a different gear oil than the 2019. I got this screenshot from the online version of the factory service manual.