Engine oil recommendations have been something of a moving target for Ram EcoDiesel owners. Here are the latest motor oil specifications for each model year. We also include high-quality AMSOIL synthetic motor oil options for EcoDiesel models.
2014-2019 EcoDiesel (Generation 2 Engine)
It took trial and error to sort out the motor oil requirements for the Gen 2 EcoDiesel engine. For the inaugural 2014 model year, a 5W-30 meeting the Chrysler MS-11106 specification was initially (and mistakenly) suggested. This motor oil spec was a low-SAPS (sulfated ash, phosphorus, sulfur) European car formula. This original motor oil choice turned out to be a miscalculation for Chrysler. Main bearing failures started cropping up and this was attributed to the light European 5W-30 spec.
By the summer of 2016, Chrysler switched the EcoDiesel to heavy-duty diesel 5W-40 meeting the MS-10902 and API CJ-4 (and later CK-4) specs. In other words, the same motor oil types as suggested for the 6.7L Cummins in the 2500 and 3500 trucks. This spec change applied to all models from 2014-forward. Chrysler stuck with this oil spec through the 2019 model year.
AMSOIL has two 5W-40 motor oil options meeting the MS-10902 specification for the Gen 2 EcoDiesel engine.
Ultra-premium– “DEO” AMSOIL Signature Series Max-Duty Synthetic Diesel 5W-40
Commercial-grade– “ADO” AMSOIL Heavy-Duty Synthetic Diesel 5W-40
2020-2021 EcoDiesel (Generation 3 Engine)
With the introduction of the Generation 3 EcoDiesel engine in 2020, a different motor oil specification was suggested. This was the Chrysler MS-12991 specification. This spec tends to apply to Full-SAPS European 5W-40 motor oils. However, some might be surprised by the fact that the MS-12991 spec was not new. This specification was created for Fiat gasoline engines several years ago.
AMSOIL’s MS-12991 offering is “EFM” AMSOIL SAE 5W-40 FS Synthetic European Motor Oil. Now, there is an asterisk next to this recommendation. In house, AMSOIL has deemed the FS European 5W-40 as carrying the MS-12991 spec since 2013. AMSOIL suggests this product for 2020-21 EcoDiesel models in their online application guide. However, this spec is not listed on the bottle label or in the product data sheet.
The reason being is that the ash content is just a few PPM off of the MS-12991 spec limit. We are talking a few “parts-per-million”. In other words, this number is so close that it’s barely measurable. Therefore, AMSOIL feels supremely comfortable recommending and warranting their FS European 5W-40 for 2020-21 Gen 3 EcoDiesel motors.
We hope that AMSOIL will tweak this formula in order to add MS-12991 to the label. Why hasn’t this happened sooner? We wonder if tuning the ash content will disrupt a Mercedes or BMW spec also carried by this product? We can tell you that the AMSOIL FS European 5W-40 can be used with confidence in ’20-’21 EcoDiesel engines. After 20 years of dealing with this company, we are very confident in this recommendation. If AMSOIL decides that a product does not meet a particular industry specification, they simply will not recommend it. They do not suggest a product that “might” work.
2022 And Newer
For the 2022 model year, Chrysler required 5W-40 motor oil that met both API SP and MS-12991 specs. API SP is a passenger car/gasoline engine motor oil standard. It is not not clear as to why the API SP has been added.
AMSOIL does not offer a product that carries both the API SP and MS-12991 specifications.
About The EcoDiesel Engine
This 3.0L diesel engine was designed by an Italian diesel engine maker called VM Motori. A little-known fact is that General Motors once owned half of VM Motori (2007-2013). The earliest iterations of this 3.0L engine were actually intended for a Cadillac model in the European market. GM’s 2009 bankruptcy ended this project and they eventually sold their stake in VM Motori. Fiat ultimately bought up VM Motori. By 2011, Fiat took controlling interest in Chrysler. This created a clear path for the eventual “Gen 2” EcoDiesel motor to make its way into RAM 1500 and Jeep Grand Cherokee models.
Where To Buy Motor Oil For EcoDiesel Engines?
Oildepot can offer elite AMSOIL synthetic motor oil options for EcoDiesel engines at wholesale prices. Contact us using the form on this page or call us at 1-800-748-5781.