Mag_Hytec Differential cover???

[GDBax47]

I have a 2019 3500 DRW/4WD. I am trying to replace my diff cover with a Mag -Hytec AA14-11.5 that I took off my 2012 3500 SRW/4WD. Without removing the old cover, the holes do not seem to line up. Even measured the side holes center to center and they are different. The dealer and my spec sheet by VIN says I have an 11.5" axle. A rep from Mag-Hytec says it's a 12" and I need their AA14-12 cover. The owners manual says I need 75W-85 gear lube for 11.5 and 75W140 for the 12". Anyone have similar experience and confusion like me. I could use some clarification please. Thanks
Greg

 

[maxx442]

The new DRW's have a 12" diff. Banks is the only one that I have heard of that is making one for the new diffs.

 

[Brutal_HO]

The base axle is 11.5 and may show as standard equipment. Since you have a DRW, you have the 12" rear and that should show on optional equipment.

The SRW HO and the DRW have the 12" rear.