Is the diff limited slip with a mechanical clutch or is it non locking or electronic locking. That's where pretty much all of it is aside from the spec likely dictating a minimum bearing wear pass and maybe cold flow and flashpoint as well. But a special additive pack is likely the primary reason for the spec.
Mopar MS-A0160 Spec for 75W-90
- Thread starter The Critic
- Start date
In my case, I have an open diff.
I have a couple new part numbers to throw into the mix from a different Chrysler dealer.
Front Diff: 5136035AD (75w85 and isn't even listed in the current lubricant and chemical catalog)
Rear Diff: 68210057AB (75w85 and isn't MS-A0160, Mopar's webstore states this is for Ram 2500s)
Last edited:
What's up with the quotes being all grayed out now.
Anyways i have never had an issue using non special cheap gear oils. Owned an f150 with a mechanical limited slip diff and used off the shelf limited slip 80w-90 and the operation was the same if i floored it with tc off. But i only did that like 5 times in it's life. No skipping or anything.
I've only ever used the cheapest conventional gear oil in my Yukon and it has almost 340k on it. Original diff and its only had 3 changes so far but I'll do the 4th soon. It's a locking diff so an additive is technically required but it's an SUV so i never get the wheels to spin so it doesn't matter that it doesn't have the additive. If i were to turn tc off and floor it then it would have issues but i have no reason to.
You could use conventional 80w-90 and change that twice as frequently as i do as conventional gear oils are half the price of synthetic and nothing bad would happen, if anything it would last longer than the average ram since some of those never see a fluid change in their lives. But the bearing wear results for conventional and synthetic 90 grade is technically big. Like half the wear rate but that matters if you tow. But i have almost 340k on my diff and there's no whining, noise, or slop or anything. Maybe those old style gm diffs were just built well.
I'd be curious to hear @High Performance Lubricants thoughts on their gear oil in this application.
I'd assume it would be fine.
I'd assume it would be fine.
Just got off the phone with Red Line tech information.
The person that I spoke with had no doubt that their 75w90 would be suitable for the MS-A0160 application, even though they don't call it out specifically.
The person that I spoke with had no doubt that their 75w90 would be suitable for the MS-A0160 application, even though they don't call it out specifically.
I doubt they even know what that spec is - they are probably going off of what their additive supplier listed in a document. It is highly unlikely that Redline field tests their oils in the applications that they recommend them for - they would not have the budget for it.
Still looking into this as it puzzles me. Looking at it from the other direction of the 2017 manual states 75w140, but has been updated.
@MattPersman do you know of any info for 2017 owners about the spec change?
Here’s a 2017 VIN if it helps 1C6RR7FG0HS760348
@MattPersman do you know of any info for 2017 owners about the spec change?
Here’s a 2017 VIN if it helps 1C6RR7FG0HS760348
Likely it’s some sort of lubricant supplier change at that time. I find Chrysler spec numbers are more internal call outs with no real testing documentation to back them up.
The team at the axle manufacturer could have changed and said fluid x is way better you must use that.
IMO any commercially manufactured tested gear oil is gonna be fine. There is no black magic involved in these basic units
The team at the axle manufacturer could have changed and said fluid x is way better you must use that.
IMO any commercially manufactured tested gear oil is gonna be fine. There is no black magic involved in these basic units
Thank you for your reply.
I'm leaning towards your last sentence as well. I find it curious that 2017 and 2018 MY trucks had 75w140 in the manual but they are not recommended at 75w90 but there isn't an associated TSB to go with it. If there was a problem that the 75w90 would "fix" or band aid, I would think there would be a TSB related to it.
Especially when I've called several dealers and ended up with a few different oil recommendations from the parts counters.
I'm leaning towards HPL. Currently debating between 75w90 and 75w110 in the rear.
My 2018 has 75W-90 in the manual.
In the book or online?
These "books" state 75w140. They're linked from Canadian sites, but appear to be applicable to US and CAN models.
Page 618
Page 281
Mine is a paper book that I requested after I bought the truck new.
