The new Cummins oil requirements

Disclaimer: Links on this page pointing to Amazon, eBay and other sites may include affiliate code. If you click them and make a purchase, we may earn a small commission.

stevenP

Senior Member
Joined
Nov 9, 2014
Posts
641
Reaction score
621
Location
northern Indiana
Ram Year
2022 2500 Longhorn
Engine
6.7L Cummins
So I had a Gen4 cummins. Now I have a Gen5 6.7L cummins in my new 2500. So I see that the recommended oil is now either 10w-30, or 5w-40. The thing is I have a lot of the rotella 15w-40 oil in jugs still. Should I not use this in the summer season?
 

06 Dodge

Senior Member
Joined
Jan 4, 2022
Posts
1,900
Reaction score
1,781
Location
Forest Grove, Oregon
Ram Year
2022
Engine
6.7L CTD
Do not use 15w40 in your engine the new lifters can not handle 15w oil or so I've been told my a few well seasoned owners and one mechanic...
 

HEMIMANN

Senior Member
Supporting Member
Military
Joined
Dec 7, 2020
Posts
6,807
Reaction score
17,098
Location
Minneapolis, MN
Ram Year
2017 2500 Laramie Crew Cab
Engine
6.4L HEMI
Do not use 15w40 in your engine the new lifters can not handle 15w oil or so I've been told my a few well seasoned owners and one mechanic...

The Gen4 went to hydraulic lifters, yes? If so, it seems oil flow is too restrictive with the traditional diesel viscosity. Perhaps they don't want the "Hemi experience" :confused:

If this is the case, let's hope they also didn't sacrifice wear as well. I thought I'd never see the day Cummins abandoned solid lifters and 15W-40 oil.
 

06 Dodge

Senior Member
Joined
Jan 4, 2022
Posts
1,900
Reaction score
1,781
Location
Forest Grove, Oregon
Ram Year
2022
Engine
6.7L CTD
The Gen4 went to hydraulic lifters, yes? If so, it seems oil flow is too restrictive with the traditional diesel viscosity. Perhaps they don't want the "Hemi experience" :confused:

If this is the case, let's hope they also didn't sacrifice wear as well. I thought I'd never see the day Cummins abandoned solid lifters and 15W-40 oil.

Before my 2022 truck arrived I did a lot of reading and asking lots of Q's, I was first was told dealer I couldn't use 5w40 that I had left over from my 06 CTD then found out that I can being its listed in owners manual, an yes I was very surprised when I found out they went away from solid lifters...
 

HEMIMANN

Senior Member
Supporting Member
Military
Joined
Dec 7, 2020
Posts
6,807
Reaction score
17,098
Location
Minneapolis, MN
Ram Year
2017 2500 Laramie Crew Cab
Engine
6.4L HEMI
Before my 2022 truck arrived I did a lot of reading and asking lots of Q's, I was first was told dealer I couldn't use 5w40 that I had left over from my 06 CTD then found out that I can being its listed in owners manual, an yes I was very surprised when I found out they went away from solid lifters...

I retired from Cummins just before 2016, and hadn't heard a peep about this.
 

06 Dodge

Senior Member
Joined
Jan 4, 2022
Posts
1,900
Reaction score
1,781
Location
Forest Grove, Oregon
Ram Year
2022
Engine
6.7L CTD
Oh my MSP just left North IA Sept 20th 2018 I sure do miss the quite life of small town IA but grandchild hated not being able to be with her only grandpa so we sold an moved to the PDX area of OR...
 

18CrewDually

Senior Member
Joined
Nov 17, 2019
Posts
2,012
Reaction score
2,584
Location
U.S.- New Jersey
Ram Year
2018
Engine
Cummins 6.7 H.O.
The Gen4 went to hydraulic lifters, yes? If so, it seems oil flow is too restrictive with the traditional diesel viscosity. Perhaps they don't want the "Hemi experience" :confused:

If this is the case, let's hope they also didn't sacrifice wear as well. I thought I'd never see the day Cummins abandoned solid lifters and 15W-40 oil.

No. Hydraulic lifters along with a new composition block was in 2019 when they changed to the ugly front end.
 

Fuel35 67

Senior Member
Military
Joined
Aug 18, 2019
Posts
311
Reaction score
194
Location
Hanford
Ram Year
2011
Engine
6.7 Cummins
That’s exactly why they are so damn quiet now. My 99’ was LOUD and my 11’ was much quieter. I guess the newer Cummins are quieter so you can place your order in the drive through without shutting off the engine.
 

HEMIMANN

Senior Member
Supporting Member
Military
Joined
Dec 7, 2020
Posts
6,807
Reaction score
17,098
Location
Minneapolis, MN
Ram Year
2017 2500 Laramie Crew Cab
Engine
6.4L HEMI
That’s exactly why they are so damn quiet now. My 99’ was LOUD and my 11’ was much quieter. I guess the newer Cummins are quieter so you can place your order in the drive through without shutting off the engine.

That was back in 2007 to meet EPA Tier 4 exhaust emission reductions. High Pressure Common Rail Fuel System with multiple injection piezo injectors. All it took was money. Lots of money.
 

Fuel35 67

Senior Member
Military
Joined
Aug 18, 2019
Posts
311
Reaction score
194
Location
Hanford
Ram Year
2011
Engine
6.7 Cummins
A cat would’ve been fine, but the EPA, which just got a long overdue spanking, said that these trucks needed to meet certain emissions standards. But yet, I haven’t seen a single way to measure diesel exhaust like it’s done with gasoline engines. EGR is the dumbest emissions screw up ever to be introduced. I’d like to travel back in time to find the guy that suggested it, then go back further and make his mom swallow!
 

HEMIMANN

Senior Member
Supporting Member
Military
Joined
Dec 7, 2020
Posts
6,807
Reaction score
17,098
Location
Minneapolis, MN
Ram Year
2017 2500 Laramie Crew Cab
Engine
6.4L HEMI
They didn't have fast injectors back then. Had to cool peak flame temp with either exhaust or water spray - pick your poison. They had no choice - EPA mandated NOx reduction.
 

tjfdesmo

Senior Member
Joined
Apr 15, 2014
Posts
2,255
Reaction score
4,038
Location
AZ
The 1500s are on Gen 5, the HDs are Gen 4.5, as they are still the same facelifted cab. The new engines are referred to as CGI(Compacted Graphite Iron)engines. Hydraulic roller lifters, scissor gear on the cam drive for noise reduction.
 

HEMIMANN

Senior Member
Supporting Member
Military
Joined
Dec 7, 2020
Posts
6,807
Reaction score
17,098
Location
Minneapolis, MN
Ram Year
2017 2500 Laramie Crew Cab
Engine
6.4L HEMI
I read all about CGI. It's nothing more than partially completed Ductile Cast Iron used in sewer pipes. They touted it like the 2nd coming of Christ. Yes it's a bit tougher than regular gray cast iron, but not that huge a deal.
 

tjfdesmo

Senior Member
Joined
Apr 15, 2014
Posts
2,255
Reaction score
4,038
Location
AZ
I read all about CGI. It's nothing more than partially completed Ductile Cast Iron used in sewer pipes. They touted it like the 2nd coming of Christ. Yes it's a bit tougher than regular gray cast iron, but not that huge a deal.
I agree 100%, but it is the primary difference touted by them. I was told by a Cummins rep at a trade show that the Ram 6.7 is the only CGI. The rest of the ISB 6.7s are still regular gray iron. AFAIK still the only version with the timing case at the front, too?
 

HEMIMANN

Senior Member
Supporting Member
Military
Joined
Dec 7, 2020
Posts
6,807
Reaction score
17,098
Location
Minneapolis, MN
Ram Year
2017 2500 Laramie Crew Cab
Engine
6.4L HEMI
I agree 100%, but it is the primary difference touted by them. I was told by a Cummins rep at a trade show that the Ram 6.7 is the only CGI. The rest of the ISB 6.7s are still regular gray iron. AFAIK still the only version with the timing case at the front, too?

Yeah, that was to take noise away from the cab. I don't know what difference it made. I know the mechanics weren't happy about it.
 

DonF

Junior Member
Joined
Feb 22, 2019
Posts
8
Reaction score
3
Location
C limax, NC
Ram Year
2016
Engine
6.6 Cummins
The '07 emission levels were a disaster for the truck manufacturers. No body was ready for that crap!
 

Nickx86

Senior Member
Joined
Jun 16, 2018
Posts
181
Reaction score
112
Location
NJ
Ram Year
2016
Engine
6.4 Hemi
The '07 emission levels were a disaster for the truck manufacturers. No body was ready for that crap!
thats why caterpillar got out of the on road diesel route…the emission **** wasn’t worth the aggravation
 

HEMIMANN

Senior Member
Supporting Member
Military
Joined
Dec 7, 2020
Posts
6,807
Reaction score
17,098
Location
Minneapolis, MN
Ram Year
2017 2500 Laramie Crew Cab
Engine
6.4L HEMI
thats why caterpillar got out of the on road diesel route…the emission **** wasn’t worth the aggravation

Yup - I remember that well. And Navistar completely f'd up in trying to do in-cylinder emissions reductions only without SCR exhaust aftertreatment. Got stuck paying fines to EPA for years.

Cummins and DD both did SCR, but the 1st system's reliability was poor. It's extremely complicated and expensive, unlike the passive 3-way catalyst in gasoline vehicles. And even then, they are getting expensive due to scarcity or the catalyst metals (platinum, etc.).

It's why I switched back from diesel to gasoline and lived with the low gas mileage. The cost of diesels went up so much, along with ultra low sulfur diesel fuel, only the commercial use people can justify it financially.
 
Top