Mopar MS-A0160 Spec for 75W-90

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2017+ Ram 1500's with the C235 Rear Axle require a different 75W-90 lube. The spec is Mopar MS-A0160. The Mopar 75W-90 product that meets this spec is not interchangeable with other 75W-90 gear lubes.

Is anyone aware of an aftermarket gear lube that meets this spec, or can advise on the reasons behind this new spec?
 
so what exactly is MS-A0160, a fuel economy spec? a long life spec who knows?

FWIW: IIRC they backspec'ed this for the 2017 that org. spec'ed 75w90 in the front and 75w140 in the rear.

So maybe this is just a way of making sure 75w90 is a decent lube.

I would think you could use amsoil 75w110 in the rear but it might be best to just use oem fluid.

Subaru did something similar they spec "extra mt" gear oil that is some odd 70w80 api GL-5 good luck finding that in less than 20liter pails.
75w90 gl-5 works just fine.

but at least you can buy the MS-A0160 in quarts.. might be worth it.. in warranty at least.
 
What is the detail on the C235. Is it a limited slip differential? Is the lube synthetic and also does it contain friction modifiers? Maybe it's a special synthetic lube with the friction modifiers included.
 
Originally Posted by Snagglefoot
What is the detail on the C235. Is it a limited slip differential? Is the lube synthetic and also does it contain friction modifiers? Maybe it's a special synthetic lube with the friction modifiers included.

Mine is a LSD, yes. SI states to use a MS-A0160 spec lube and also add 5oz of friction modifier.
 
I just sent an inquiry to Amsoil asking if their 75W-90 is appropriate for this application.
 
I just sent an inquiry to Amsoil asking if their 75W-90 is appropriate for this application.
As expected, Amsoil recommends using their 75W-90 in this application with no addition of friction modifier. They did not offer any additional info regarding this spec.
 
Per my local dealer, by VIN, my rear differential calls for part# 68218655AC which is compatible for MS-9763 and not MS-A0160. This contradicts the information found in the owner's manual. I have reached out to RAM Customer Care for clarification.

Also, the 2020 Mopar Chemical Guide has the following information about part # 68218655AC:
" Specifically formulated for improved fuel efficiency while providing exceptional antiwear properties. For use in all FCA US LLC corporate axles. "

Not sure if one is supposed to supercede the other.
 
For anyone else looking at this. I talked to Michael about it. I’m a tech at an FCA dealer , not an engineer or spokesman, or even remotely an expert. Just a car guy who is also trying to learn about oils here.

Per our message I said I would use the 665ac fluid

The service information for your truck (which FCA claims is always the newest information) says to use that 665ac fluid as of this week anyways

They are seemingly changing fluids recommendations quite often in my eyes behind the wrench, either mileage, weight, part number etc. things seem to change frequently. It could be a vendor issue more than anything. A new guy perhaps is representing the axle vendor and likes blank fluid cause instead of what the last guy liked. Not sure about the behind the scenes

Really hard to go wrong with amsoil or redline either for pretty much any fluid.
 
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As expected, Amsoil recommends using their 75W-90 in this application with no addition of friction modifier. They did not offer any additional info regarding this spec.

Fill up with AMSOIL SG 75W-90 when your truck is due for a change. And then forget about diff lube for the next 100,000 miles (y)
 
Wanted to circle back on this thread....Amsoil no longer has a recommendation. I emailed their support and they would not recommend Severe Gear 75W-90 for my 2018 Ram.
 
Wanted to circle back on this thread....Amsoil no longer has a recommendation. I emailed their support and they would not recommend Severe Gear 75W-90 for my 2018 Ram.
Amsoil may not be aware of the new FCA recommendation to use part# 68218655AC, which is the standard FCA 75W-90 gear oil.
I have been using Redline 75W-90 on mine for the last 600 miles with no issues and I did not have to add any extra friction modifier. Redline has not withdrawn their recommendation for this application, either.
 
Pretty surprising that this is the only thread about the MS-A0160 spec.

Has anyone learned anything more about this spec and the fairly radical change that Chrysler made for this differential?
 
Most synthetic 75w90 gear oils have LS friction modifier in them already, so any of them can be used in limited slip or other axles calling for 75w90 GL5
 
I put Valvoline synthetic 75W-90 in my 2018 rear diff.

It seems that many do and are fine. It's just a really curious spec, IMO.

Especially when AMSOIL isn't saying their stuff is recommended for it.

Most synthetic 75w90 gear oils have LS friction modifier in them already, so any of them can be used in limited slip or other axles calling for 75w90 GL5

I don't believe this spec is related to the friction modifier at all. I don't have a LSD.
 
I called Valvoline because they list their full synthetic as suitable for this application.

The person I spoke with said that the spec is a standard GL5 75w90 w/limited slip additive. I said, that’s the same spec we’ve been using for decades. So, Valvoline’s stance is this is not a special spec.
 
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