New 4th gen diff cover

[Randomrunner12]

Hey guys,

I'm going to be getting a magtec diff cover for my sig truck. Wondering if I need to run the amsoil severe duty 75w-90 or if I will be ok with just the amsoil 75-90 synthetic.

Any input would be great.

Tackling full brakes and flush, trans, diff, oil fluids and adding temps sensors to diff and trans with tax return.

 

[CMB]

Diff fluid needs to be GL-5 rated. I don't think it matters as long as it complies with that standard and is synthetic. Although I'm not sure if a dino 75w-90 would meet GL-5. Hmmmm.

 

[Cummins12V98]

I would go with the best they have, SevereGear. If you tow heavy or a lot go with the 75-110.

 

[6V92TA]

RandomRunner, you will be OK with any brand. 7590 or 85140. its one of those things where a difference makes no difference.. just like motor oil.

 

[Jim W]

Hey guys,

I'm going to be getting a magtec diff cover for my sig truck. Wondering if I need to run the amsoil severe duty 75w-90 or if I will be ok with just the amsoil 75-90 synthetic.

Any input would be great.

Tackling full brakes and flush, trans, diff, oil fluids and adding temps sensors to diff and trans with tax return.

I would use the Amsoil Severe Gear Synthetic differential fluid. Use either 75W-90, 75W-110 or75w-140 for both the front and rear differentials. Changing the oil per Rams maintenance schedule. Keep in mind when refilling the Mag-Hytec cover this will hold more oil than stock. Amsoil also sells a hand pump and hose to fill your differential for $9.95 US. I have used this and it does make it easier to fill the Differential up.

I also tow heavy and I run the 75W-90 Severe Gear lube with front and rear Mag-Hytec covers changing the differential oil every 40K on my truck. I use the 75W-90 for fuel economy reasons. I also measure the diff oil at every rest stop with an IF heat gun, when towing my temps are between 135F and 145F.

 

[jelag]

I had a slight shudder when pulling away from a stop sign on a slight hill.... like when you pull off a freeway interchange and go over the freeway... BTW only when towing... I was sure this was the transmission when I finally sorted it out and realized it was only when making a turn... so I acquired the 75W-110 and installed it.. the Amsoil reference guide shows the 75W-110 as the recommended sever duty fluid...

After installing the fluid the shudder went away... My big surprise was the OE fluid only had 50K miles on it at the time...

 

[Cummins12V98]

RandomRunner, you will be OK with any brand. 7590 or 85140. its one of those things where a difference makes no difference.. just like motor oil.

NOT true, the OE GL for example does NOT hold up. Binding at 15K on take off on turns towing is NOT acceptable.

Look up your fitment on AMZ/OIL's site and they will show 75-90 along with 75-110 on the 13 and newer trucks.