5W40 or 15W40 in 6.7 CTD?

[BurbMan]

So the owner's manual in my 2015 Ram says to use 15W40 oil in the 6.7 Cummins diesel, unless the temp is going to routinely be below 0*, in which case you should use 5W40.

Here on Long Island, the temp rarely if ever even gets to 0*, much less stays under it for any period of time. I'm coming up on my first oil change since I've owned the truck, and I was all set to stay with 15W40. However, guys on a couple forums are saying they use 5W40 year round.

Please let's not get into a brand war or discussion about dino vs. synthetic, but I'm interested to know what weight oil you guys are using.

[rhagfo]

LIKE2BUILD wrote:

ShinerBock wrote:

LIKE2BUILD wrote:

otrfun wrote:
Sounds like a perfectly legtimate explanation to me. If this is the case, gotta wonder what specific issue in that 6 mo. to 12 mo. MTBF/OCI data pushed their warranty costs high enough to warrant a 6 mo. OCI? Hhhmmm . . .

$$$$ is part of the explanation. They are hoping you bring your shiny new Ram back to the dealer for that 6 month service. They are going to charge you $150+ for an oil change that costs less than $85 for oil and filter. Oh, and there's always the up-sell of other services that a lot of people buy once they're in the door.

KJ

This is true as well! And there are many gullible owners than do not know any better that will follow suit without question

Service departments are a big money maker for dealerships, and it's all about the up-sell. We looked at a Camry years ago and the salesman told us all about the reliability, longevity, etc. Then when we started talking numbers it turned to the amazing service department and extended warranty purchase options. Service? Extended warranty? Wait a minute, didn't you just tell me these cars are extremely reliable?

It's all the same game. Get you in the door, get you on the hook to buy the vehicle or pay for a service, then start adding all the little things "you really need" to make it complete. The worst game is to get you in the middle of a service then they bring you some part (or call you) and convince you something else must be done to drive the car away. Now they really have you behind the 8-ball. Sure, there are times when you start the work and find something else connected that has to be done. But to a great degree that middle of the service, dire warning is just part of the up-sell game. That's one primary reason I've done nearly all of my own service and repairs for years.

KJ

I took our 2006 PT Cruiser in for an oil change, some kind of dealer deal to get me in the door. Pointed out leaking PS return line, $200+ For them to fix. Took it home looked at the leak, got out my hose band crimping pliers, gave a squeeze and leak fixed!
I have done most of my own repairs since I got my first car. Did it then to save money, as I got older wanted it done right, now it is do it right and therapeutic.

[LIKE2BUILD]

ShinerBock wrote:

LIKE2BUILD wrote:

otrfun wrote:
Sounds like a perfectly legtimate explanation to me. If this is the case, gotta wonder what specific issue in that 6 mo. to 12 mo. MTBF/OCI data pushed their warranty costs high enough to warrant a 6 mo. OCI? Hhhmmm . . .

$$$$ is part of the explanation. They are hoping you bring your shiny new Ram back to the dealer for that 6 month service. They are going to charge you $150+ for an oil change that costs less than $85 for oil and filter. Oh, and there's always the up-sell of other services that a lot of people buy once they're in the door.

KJ

This is true as well! And there are many gullible owners than do not know any better that will follow suit without question

Service departments are a big money maker for dealerships, and it's all about the up-sell. We looked at a Camry years ago and the salesman told us all about the reliability, longevity, etc. Then when we started talking numbers it turned to the amazing service department and extended warranty purchase options. Service? Extended warranty? Wait a minute, didn't you just tell me these cars are extremely reliable?

It's all the same game. Get you in the door, get you on the hook to buy the vehicle or pay for a service, then start adding all the little things "you really need" to make it complete. The worst game is to get you in the middle of a service then they bring you some part (or call you) and convince you something else must be done to drive the car away. Now they really have you behind the 8-ball. Sure, there are times when you start the work and find something else connected that has to be done. But to a great degree that middle of the service, dire warning is just part of the up-sell game. That's one primary reason I've done nearly all of my own service and repairs for years.

KJ

[ShinerBock]

LIKE2BUILD wrote:

otrfun wrote:
Sounds like a perfectly legtimate explanation to me. If this is the case, gotta wonder what specific issue in that 6 mo. to 12 mo. MTBF/OCI data pushed their warranty costs high enough to warrant a 6 mo. OCI? Hhhmmm . . .

$$$$ is part of the explanation. They are hoping you bring your shiny new Ram back to the dealer for that 6 month service. They are going to charge you $150+ for an oil change that costs less than $85 for oil and filter. Oh, and there's always the up-sell of other services that a lot of people buy once they're in the door.

KJ

This is true as well! And there are many gullible owners than do not know any better that will follow suit without question.

This kind reminds me of a friend who traded in his VW Tiguan for an Audi Q3 which is essentially the same thing with the same engine, but the Tiguan is slightly detuned. Even though they were basically the same, the Audi had a laundry list of extra maintenance items that the dealer would throw at him every time he came in for an oil change that they did not with his Tiguan. I guess they assume that people who buy such vehicles are more gullible and/or are less concerned about such things.

The local Infiniti dealer tried to do the same with my wife not too long ago. She went in for a 50k mile service and tried to tell her that she needed to replace all of the coolant hoses and a list of other things totaling over $750. I told her to hand her phone over to the service writer after she told me this, and I told him that if this SUV needs all of this at at 50k then Nissan/Infiniti must used cheap parts and the vehicles is a pile of junk. No vehicle I have ever owned has needed this kind of stuff at 50k, and that I will be trading it in if that is the case. It was after this that he changed his tune and said it was "recommend" not needed like he was telling my wife to scare her into paying.

Although at first he was trying to explain why it was needed, but I then told him my background and what I do for a living and he stopped after figuring out that I probably know more about engines and vehicle than he does.

[LIKE2BUILD]

otrfun wrote:
Sounds like a perfectly legtimate explanation to me. If this is the case, gotta wonder what specific issue in that 6 mo. to 12 mo. MTBF/OCI data pushed their warranty costs high enough to warrant a 6 mo. OCI? Hhhmmm . . .

$$$$ is part of the explanation. They are hoping you bring your shiny new Ram back to the dealer for that 6 month service. They are going to charge you $150+ for an oil change that costs less than $85 for oil and filter. Oh, and there's always the up-sell of other services that a lot of people buy once they're in the door.

KJ

[ShinerBock]

otrfun wrote:
Sounds like a perfectly legtimate explanation to me. If this is the case, gotta wonder what specific issue in that 6 mo. to 12 mo. MTBF/OCI data pushed their warranty costs high enough to warrant a 6 mo. OCI? Hhhmmm . . .

I don't think it is a specific issue per say, but rather a way to get out of paying if they the owner is stupid enough to tell them. That would be the only way they would find out since they would never know with a UOA. I can see why the old 2007.5-2012 Ram Cummins engines with out DEF would need a 6 month interval due to contamination from how often the EGR is being utilized, but not the 2013+.

Here is another ISB/B-series maintenance guide realized by Cummins for motorhomes that was updated in Dec-2018 for the new engines as well. While the "new" engines did not show up in Ram's until 2018, they were already in other applications since 2017.

Motorhome Maintenance and Operation
B6.7TM, ISB6.7, ISB5.9, B5.9 Engines (200-360 hp)

[otrfun]

ShinerBock wrote:

otrfun wrote:

ShinerBock wrote:

blofgren wrote:

It would probably make no difference as long as you aren't exceeding the mileage specifications. I'm not the least bit worried about the 1 year OCI that I have been using for several years now.

You are correct. The time frame of 6 months doesn't matter as long as it is changed with a certain mileage or engine hours. As I stated earlier, no oil analysis would be able to tell the difference between 15k mile oil at 6 months or 15k mile oil at 12 months. The 15k interval with the Cummins is even with non-synthetic 15w40.

Makes perfect sense to me.

Then why the heck does Ram have a 6 mo. OCI on their late model Cummins?

They have "severe" duty maintenance intervals for other things like the tranny and differential. Why wouldn't they recommend 6 mo. OCI's for severe duty and 12 mo. for non-severe?

Ram obviously feels there's something that's degrading the oil over time---something that's not mileage related. Some kind of water, corrosion, or fuel contamination issue?

In my opinion it has to do with the fact that Ram owns the warranty of the engine from Cummins. Unlike the medium/heavy duty world where even though the truck is a Peterbilt, Kenworth, and so on, you still have to go through Cummins for the engine warranty, not the vehicle manufacturer. The same holds true for other engines such as Caterpillar, Detroit Diesel, and so on.

For example, if a Peterbilt with an ISB6.7 comes into our service department with an engine issue under warranty, we file the claim with Cummins, not Peterbilt. Also, if that same Peterbilt went to a dealership for another make, say Freightliner, with the same engine issue. That Freightliner dealer can still perform the warranty work since the warranty is with Cummins, not Peterbilt. They can go to any dealership that is certified by Cummins to work on that engine regardless of make. If my technician is ISB certified, then he can can work on any ISB engine warranty regardless of what vehicle it is in(aside from Ram).

This is not the case with Ram. Ram essentially purchases and owns the 100k mile warranty as a part of their contract meaning I cannot take it anywhere else, even a Cummins service center, to perform the warranty. So they can decide to make the warranty more stringent than what Cummins has in other applications that are similar if they want to keep them from paying. Basically, they are stacking the deck in their favor so they will not have to pay out at the expense of the owners even though most owners do not fall within the severe 6 month duty cycle and Cummins has 12 months for similar duty cycles.

I will also say to never ever get your parts from a Mopar dealer. They mark them up 100-200% over what a Cummins dealer or even other medium/heavy duty dealers charge. For example, a Mopar dealer quoted me a Cummins water pump for $200 and it was the exact same one from Cummins my company(a medium/heavy duty dealership) sold for $65 at the time. They were both in the same Cummins box, but the Mopar had an extra sticker with a Mopar part number on it.

Sounds like a perfectly legtimate explanation to me. If this is the case, gotta wonder what specific issue in that 6 mo. to 12 mo. MTBF/OCI data pushed their warranty costs high enough to warrant a 6 mo. OCI? Hhhmmm . . .

[ShinerBock]

otrfun wrote:

ShinerBock wrote:

blofgren wrote:

It would probably make no difference as long as you aren't exceeding the mileage specifications. I'm not the least bit worried about the 1 year OCI that I have been using for several years now.

You are correct. The time frame of 6 months doesn't matter as long as it is changed with a certain mileage or engine hours. As I stated earlier, no oil analysis would be able to tell the difference between 15k mile oil at 6 months or 15k mile oil at 12 months. The 15k interval with the Cummins is even with non-synthetic 15w40.

Makes perfect sense to me.

Then why the heck does Ram have a 6 mo. OCI on their late model Cummins?

They have "severe" duty maintenance intervals for other things like the tranny and differential. Why wouldn't they recommend 6 mo. OCI's for severe duty and 12 mo. for non-severe?

Ram obviously feels there's something that's degrading the oil over time---something that's not mileage related. Some kind of water, corrosion, or fuel contamination issue?

In my opinion it has to do with the fact that Ram owns the warranty of the engine from Cummins. Unlike the medium/heavy duty world where even though the truck is a Peterbilt, Kenworth, and so on, you still have to go through Cummins for the engine warranty, not the vehicle manufacturer. The same holds true for other engines such as Caterpillar, Detroit Diesel, and so on.

For example, if a Peterbilt with an ISB6.7 comes into our service department with an engine issue under warranty, we file the claim with Cummins, not Peterbilt. Also, if that same Peterbilt went to a dealership for another make, say Freightliner, with the same engine issue. That Freightliner dealer can still perform the warranty work since the warranty is with Cummins, not Peterbilt. They can go to any dealership that is certified by Cummins to work on that engine regardless of make. If my technician is ISB certified, then he can can work on any ISB engine warranty regardless of what vehicle it is in(aside from Ram).

This is not the case with Ram. Ram essentially purchases and owns the 100k mile warranty as a part of their contract meaning I cannot take it anywhere else, even a Cummins service center, to perform the warranty. So they can decide to make the warranty more stringent than what Cummins has in other applications that are similar if they want to keep them from paying. Basically, they are stacking the deck in their favor so they will not have to pay out at the expense of the owners even though most owners do not fall within the severe 6 month duty cycle and Cummins has 12 months for similar duty cycles.

I will also say to never ever get your parts from a Mopar dealer. They mark them up 100-200% over what a Cummins dealer or even other medium/heavy duty dealers charge. For example, a Mopar dealer quoted me a Cummins water pump for $200 and it was the exact same one from Cummins my company(a medium/heavy duty dealership) sold for $65 at the time. They were both in the same Cummins box, but the Mopar had an extra sticker with a Mopar part number on it.

[otrfun]

ShinerBock wrote:

blofgren wrote:

It would probably make no difference as long as you aren't exceeding the mileage specifications. I'm not the least bit worried about the 1 year OCI that I have been using for several years now.

You are correct. The time frame of 6 months doesn't matter as long as it is changed with a certain mileage or engine hours. As I stated earlier, no oil analysis would be able to tell the difference between 15k mile oil at 6 months or 15k mile oil at 12 months. The 15k interval with the Cummins is even with non-synthetic 15w40.

Makes perfect sense to me.

Then why the heck does Ram have a 6 mo. OCI on their late model Cummins?

They have "severe" duty maintenance intervals for other things like the tranny and differential. Why wouldn't they recommend 6 mo. OCI's for severe duty and 12 mo. for non-severe?

Ram obviously feels there's something that's degrading the oil over time---something that's not mileage related. Some kind of water, corrosion, or fuel contamination issue?

[ShinerBock]

blofgren wrote:

It would probably make no difference as long as you aren't exceeding the mileage specifications. I'm not the least bit worried about the 1 year OCI that I have been using for several years now.

You are correct. The time frame of 6 months doesn't matter as long as it is changed with a certain mileage or engine hours. As I stated earlier, no oil analysis would be able to tell the difference between 15k mile oil at 6 months or 15k mile oil at 12 months. The 15k interval with the Cummins is even with non-synthetic 15w40.

[noteven]

Cold 5W40 vs 15W40

Cold oil comparison

[Cummins12V98]

I have a Blackstone report for all oil changes. All but last one have been 15k. They say I can go longer after warranty is up.

I run AMZ/OIL Signature Series 15/40. Cold pour point is not much different than their 5-40.

[rhagfo]

blofgren wrote:

otrfun wrote:

LIKE2BUILD wrote:

otrfun wrote:

LIKE2BUILD wrote:
. . . Another point for me is oil change frequency. The manual says to change oil every 15,000 miles or 500 hours and I don't even come close to that mileage in a year. So, I just change my oil once a year and with the 5W40 I'm covered for any temperature range and I don't have to worry about it.

KJ

Our 2016 Ram Cummins OCI is 15,000 mi., 500 hours, or 6 months, whichever comes first. Your profile says you have a 2014 Ram Cummins. Is the OCI different for the 2014's?

You're right, it does say 6 months. However, I'm comfortable with the additive packages in the synthetic oil and use the 1 year time frame. When I changed oil this summer I had only put 5,200 miles on the truck since July of 2019. If I would have changed oil at 6 months it would have been less than 25% used (on a mileage basis).

KJ

I was just curious, thanks. We have an 8y/120k OEM extended warranty, so we'll be sticking with the 6 mo. OCI for a few more years/miles. If we still have the truck after 8/120 we'll probably go to a 12 mo. OCI using 5w-40.

With that being said, gotta wonder which would keep my Cummins runnin' the longest? 15w-40 changed every 6 mo. or 5w-40 changed every 12 mo.? lol! 🙂

It would probably make no difference as long as you aren't exceeding the mileage specifications. I'm not the least bit worried about the 1 year OCI that I have been using for several years now.

Well, diesels don't destroy oil the same as gas, think gas is a solvent, diesel is an oil.
Our 2001 Ram 2500 CTD ran 15-40 Delo 12 months, 10K miles, had TBN tested to get there comfortably. The last test Blackstone stated plenty of additives left, go for 12,500, I stuck to 10K.
Earlier I added pictures of the tappet gallery when I needed to change the cover gasket at 300K, very clean!
I am seriously considering going by the change indicator, and spend the extra $10 for the TBN, and keep the results if there is an issue.

This six months I put 7,676 miles on the oil, and the change indicator was half way to change.

[blofgren]

otrfun wrote:

LIKE2BUILD wrote:

otrfun wrote:

LIKE2BUILD wrote:
. . . Another point for me is oil change frequency. The manual says to change oil every 15,000 miles or 500 hours and I don't even come close to that mileage in a year. So, I just change my oil once a year and with the 5W40 I'm covered for any temperature range and I don't have to worry about it.

KJ

Our 2016 Ram Cummins OCI is 15,000 mi., 500 hours, or 6 months, whichever comes first. Your profile says you have a 2014 Ram Cummins. Is the OCI different for the 2014's?

You're right, it does say 6 months. However, I'm comfortable with the additive packages in the synthetic oil and use the 1 year time frame. When I changed oil this summer I had only put 5,200 miles on the truck since July of 2019. If I would have changed oil at 6 months it would have been less than 25% used (on a mileage basis).

KJ

I was just curious, thanks. We have an 8y/120k OEM extended warranty, so we'll be sticking with the 6 mo. OCI for a few more years/miles. If we still have the truck after 8/120 we'll probably go to a 12 mo. OCI using 5w-40.

With that being said, gotta wonder which would keep my Cummins runnin' the longest? 15w-40 changed every 6 mo. or 5w-40 changed every 12 mo.? lol! 🙂

It would probably make no difference as long as you aren't exceeding the mileage specifications. I'm not the least bit worried about the 1 year OCI that I have been using for several years now.

[Grit_dog]

^Honestly, the chance of oil related failure being the first thing that gives up the ghost or causes you to buy a new vehicle is highly unlikely even with “normal” OCIs.