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.