6 Month Oil change??

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Ummmm, OK, but Cummins isn't providing your warranty. Again, your money & your choice.

Rusty

Yes, I understand that. What I asked originally was "WHY?" It appears the only reason is a HIGHLY unlikely engine failure that could be blamed on following the Cummins change reccommendation.
I do understand the moisture factor but doubt that with my driving habits and climate there is an exposure. I am going to do an oil test at six months from change to satisfy my curiosity. If it shows jp as questionable then I will change my opinion. Strictly a P&L issue!
 
So far the only reason for the 6 month stipulation is to CYA for the warrantee? So what is the Oil Life in the EVIC for? I changer my oil and filter yesterday at 7500. The EVIC showed 20% life remaining. The 'in service' date was Dec 20, 2013. (Used Stratoprore 16035 and Delo 400LE just like I did for years on my 2001)

On my new 2014 Passat TDI there was a 30 day look-see provided by the VW dealer. When I got the car back he said "See you in 1 year or 10,000 miles for the first oil change." So if the oil is older than 6 months in a Cummins, does it actually break down? But not in a VW? I understand that they are different animals, but still in the same family.

My EcoDiesel owners manual says the same as your VW dealer. It says in one part "as indicated by oil change indicator system" and in another part "NOTE: Under no circumstances should oil change intervals exceed 10,000 miles (16,000 km) or 12 months, whichever comes first". When I back calculate the current miles on this oil (still the factory fill) versus what the indicator says for remaining life it works out that I should get exactly 10,000 miles on this oil. This run would be +90% unloaded highway miles, possibly the best case scenario as far as the engine and oil life is concerned.

I did the same type of back calculation on my Dually yesterday before I did the first oil change. It was at 60% remaining life, not quite 6000 miles on the oil, but my six months was up. The calculation worked out (at the rate I was going) that I would have got exactly 15,000 miles on that oil. The run on that oil was 100% loaded highway miles with about 4000 pounds of camper in the box and frequently a 2000 pound motorcycle trailer in tow. Possibly this too was the best case scenario as far as the engine and oil life is concerned (loaded highway miles) but it makes me wonder if these Engine Oil Indicator System's really are based on anything other than a mileage count down timer since the last reset. I know my 2011 did not work this way and it really was affected by the type of driving I did.

I changed the Dually oil yesterday for 3 reasons 1) The truck's a large investment and a premature first oil change is never a bad thing. 2) I want to maintain my warranty, and the book says 6 months maximum. 3) The truck was manufactured June 2013. I figure it was probably on the lot up here in Alberta by August 2013. I didn't buy the truck until April 2014. However you count the months since the truck was built, and the engine was assembled, filled with oil and run before the truck was built, that oil was at least 11 months old before I even got the truck and I guarantee it was not changed by the dealer before I picked it up. I wouldn't have chose to buy a truck that sat like this but I was in a pinch for a shortbox dually for the camper I already had and this one fit the bill. Am I worried about the engine because of this...not at all. It's on warranty, it had an excellent quality factory oil fill, and basically no test-driving mileage when I bought it. So I counted 6 months from my in-service date and have changed the oil like I'm suppose to. Do I think it's overkill every 6 months, yes I do, and if I still have this truck when the warranty expires I will start changing the oil annually unless the EVIC or mileage has me doing it before the year is up.

Sometimes I wonder how much thought and accuracy is actually put into the writing of these owners manuals that we live by for our trucks health. It would be interesting to hear from Chrysler as to why the VM oil can hang around for 12 months but the CTD oil gets shown the door at 6 months!
 
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Ummmm, OK, but Cummins isn't providing your warranty. Again, your money & your choice.

Rusty

If you make use of Cummins Quickserve, you will find a table on there for oil changes. Their manual is quite a bit more generic, but according to their manual, the ISB has a service interval of:
25,000 miles / 1,000 hours / 6 months.
That is under normal duty cycles (according to them, over 11.5 mpg). Anything less is severe duty and that constitutes a change out of:
high
15,500 miles / 1,000 hours / 6 months.

low
5,000 miles / 1,000 hours / 6 months.

Strangely for RV's and firetrucks, they allow 1,000 hours or 12 months. (Rv's have a 25,000 mile change while fire trucks have no mileage change specified, probably because they hardly are ever driven so a yearly change is sufficient).

So RAM is already assuming the worst with their oil change-out off 15,000 miles. However, I also believe the standard ISB motor has a far larger pan than what we have in our trucks (I think something like 24 qts versus our 12 qts).
 
RVs and fire apparatus normally have larger oil pans than our Ram trucks. If you double the oil capacity, all else being equal, you double the change interval.

Rusty
 
^^^ Sorry about that Rusty, I meant to quote Al in my reply since he was stating that Cummins doesn't care about 6 months in other applications. I just wanted to show that they indeed have a date-based countdown on their motors depending on implementation. But you're also right on the larger pans. I took the opportunity to look at one of our hybrid ISB powered buses and it has a sump size of just about 20 quarts. So RAM has a smaller mileage interval for a good duty cycle because of the smaller pan. However, I think RAM assumes just about anything is a good duty cycle for their truck because it would take a lot to actually put the Cummins through its paces and make it a "Severe" duty cycle (getting less than 11.5 mpg). So I wonder if the oil countdown timer would cycle lower sooner if someone towed big in a metro city setting with a RAM (that's the worst case I can think of).

Also decided to cruise the quickserve site a little more and found some of these gems that I think people would be interested in for the ISB's implementation

Standard sump size for Cummins ISB: 15 quarts (system holds 17.6 quarts)
bigger sump size: 18.5 quarts (20.5 quarts) <-- what a hybrid bus seems to have
High Volume sump size: 25.3 quarts (system holds 27.9 quarts)

Maximum acceptable oil temperature: 280F <-- that's really hot!
Minimum oil pressure @ low idle: 10psi
Minimum oil pressure @ rated power rpm: 30psi
Oil pressure regulator @ oil pump: 75psi
Oil filter pressure delta to open bypass: 50psi <--I bet this is why we typically only see around 50 psi on our EVIC
Oil filter capacity: 1 quart

Maximum engine overspeed for 15 seconds: 4200 rpm <-- didn't think they would allow that much
Altitude Maximum: 12,000 ft <-- surprised they spec this!

Cooling system specs
Engine Capacity: 2.6 gallons (the rest is in radiator hoses and radiators)
Thermostat Range: 180 to 198 degrees F
Maximum allowed operating temp in automotive operations: 212 degrees F
 
So, with a bigger oil sump low mileage oil lasts longer?

I don't know if that's intended to be a sarcastic remark or not, but I'll give it a serious answer in case it's not. In general terms, if sump capacity is doubled, the oil change interval (based on miles or operating hours) would be approximately doubled, all else being equal. It has nothing to do with calendar hours - go back to the Cummins recommendation cited above.

Rusty
 
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I don't know if that's intended to be a sarcastic remark or not, but I'll give it a serious answer in case it's not. In general terms, if sump capacity is doubled, the oil change interval (based on miles or operating hours) would be approximately doubled, all else being equal. It has nothing to do with calendar hours - go back to the Cummins recommendation cited above.

Rusty
Actually both! I can certainly understand the interval based on miles, but with lower usage why would more oil last longe? Don't make sense. Written by two different engineers from two diffferent departments that don't communicate?
 
Sometimes I wonder how much thought and accuracy is actually put into the writing of these owners manuals that we live by for our trucks health. It would be interesting to hear from Chrysler as to why the VM oil can hang around for 12 months but the CTD oil gets shown the door at 6 months!

Same hear, so many contradictions in the manual.
 
Actually both! I can certainly understand the interval based on miles, but with lower usage why would more oil last longe? Don't make sense. Written by two different engineers from two diffferent departments that don't communicate?

In regards to the 6 month oil life. This is based in regards to the worst in having condensation and low-mileage/low-usage driving. If you double the sump, you have more additive to effectively combat oil acidification. Acidification happens as oil takes in water and isn't able to "Burn it off". Water formation can happen from condensation from the cylinder walls or humidity from air being sucked in and blown into the crank case. This is why when you send oil in for oil analysis to determine lifespan, you pay extra for a "Total Base Number" or "Total Acid Number" analysis (TBN or TAN). This helps determine whether or not your oil has enough additive to combat acidification given your own duty-cycle. Remember, the recommendations are written for a very general audience and they need to cover their uses. RAM knows that they have lots of users that push a RAM to its max or drive infrequently and they account for those guys given the oil change schedule of 6 months. A 1500 will not see the duty cycle of a RAM 2500/3500 as most people with half-tons also use them as daily drivers. That isn't always the case with HD trucks. You have your hot-shotters and your RV haulers.

Another thought in the whole water condensing issue is that the Cummins I-6 has far more surface area of block material exposed versus a "V" engine where only the outer side of each bank of 4 cylinders is really exposed. In the case of the VM Motori, it's the outer bank of each of 3 cylinders. Also, the VM engine does burn hotter than the Cummins, so maybe it has an easier time burning off accumulated moisture as well. I'm sure there are other factors that Cummins attributes and compensates for in that 6 month oil change interval, however when my warranty is up, I plan on doing oil analysis to figure out how far I can really stretch my oil changes date wise. I'm figuring I can go the full 15k miles with no issue (that would be a yearly change for me).
 
Are you saying that moisture get in through the BLOCK??????

Remember what cummins sez: http://cumminsengines.com/cummins-turbo-diesel-2013?Filters=0&Categories=103#overview FOR OUR PICKUPS!!

Hi Al, the specs that I sighted earlier are specs from Cummins Quickserve which is their technician material when it comes to determining service I interval and procedure. I feel it is more authoritative than their marketing material. Remember also, the 6 month oil change is probably to account for more extreme cases of certain usage, while the evic will account for severe duty cycle when in use, it will not account for time when just sitting there. If the conditions are right from infrequent engine usage, you may have a recipe for condensation. If there is any combustion byproduct in the oil and water, you will have oil acidification and this is what they are guarding against. Quick serve is free for an owner with a vehicle limit if 5. Check it out.
 
well, I bought it on Feb 6th, and changed the oil for the first time on December 6th..! 10 months to the day.. truck has 8500 miles on it. Good thing too after dealing with whatever idiot thought THAT was a good way to bury the oil filter!
 
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