2 Years Without Changing Oil?

JimK-NY wrote:
I bought my 2018 Ram diesel in the Summer of 2018..

..The oil changes are supposed to be at 15,000 so I took it in for an oil change and they also changed the fuel filters. The dealer charges were just over $700!!!!!..

..I spent a lot of time with online research on this issue. If the warranty had not been a consideration I would not have even bothered with the oil change. Based on mileage and test results, 15,000 miles is very conservative. When condensation is not an issue, oil does not age at least over the period of a couple of years or so. Since I have been thoroughly warming up the engine that is not a concern either. I even wonder about water in the oil for short trips. How does water enter the system?

Dealer AND not just an oil change but oil change on a Diesel PLUS FUEL FILTERS on said Diesel = EXPENSIVE!

Yeah,dealer labor is not cheap, figure at a min of $120 possibly $150 PER HR.

Diesel fuel filters are insanely expensive.. I would hedge a bet that a OEM RAM fuel filter would cost you north of $150 if you bought one at the dealer..

Found a Mopar branded diesel filter kit (both filters) for $103 HERE

So, yeah, having them change the diesel filter most likely padded the bill by $150-$200 for filters plus the additional labor over top the oil change..

But, yeah $700 for oil change and fuel filter change is very pricey, but you do always have the DIY angle to save some change..

I try to avoid having dealer do my work whenever possible..

Moisture in the engine oil, pretty much most of that comes from blow by past your rings, moisture is a byproduct of any combustion process.. Some can come from the air from expansion/contraction that happens from hot to cold, the crankcase is not exactly 100% sealed, there is some allowance for the air in the crankcase to equalize in pressure with the outside air.. That process can bring in some moisture laden air into the crankcase..

Diesel fuel can also pickup moisture from the air..

jdc1 wrote:
LOL. Those 2018 cars sitting on the lots at your local dealer? They won't/don't change the oil just because it's a year old. Heck, that can of oil you just bought could be 5 years old....there's no expiration date on it....never has been, never will be.

They are also not "starting" those vehicles sitting on those lots for a yr either.. Often on those long term sitters they have to give them a battery jump start (yeah, I have seen that).

That does make a huge difference.

When you start ANY engine there is something called "blow by", that is a small leakage of burned and unburned gasses that get by the rings. Some of those gasses also condense on the cylinder walls and the oil control rings whisk that away and eventually that makes it's way down into the oil pan. That is normal and I would be concerned if there was not a slight leakage that would mean the rings were sized to tight..

That leakage is also greater when the engine is stone cold which is when the rings are at the smallest tolerances.. As engine and rings warm up, things expand and creates a better seal reducing "blow by" some..

You can easily store a engine for many years with oil in it with no harm as long as you changed it before storing and the oil was not old dirty used oil..

LOL. Those 2018 cars sitting on the lots at your local dealer? They won't/don't change the oil just because it's a year old. Heck, that can of oil you just bought could be 5 years old....there's no expiration date on it....never has been, never will be.

I bought my 2018 Ram diesel in the Summer of 2018. I took a 4 month RV trip and drove 13,500 miles. I start up the RV about once a month and make sure it warms up thoroughly before shutting it off. After of year I had added about 500 miles for a total of 14,000 miles. The oil changes are supposed to be at 15,000 so I took it in for an oil change and they also changed the fuel filters. The dealer charges were just over $700!!!!!

A year later I still have not gone anywhere significant due to Covid. I am still just short of 15,000 miles. To preserve the warranty I decided to change the oil myself. The oil and drain pan cost me about $75 (Rotella T6). The filters are poorly located and seemed difficult to replace so I have not done them.

DEF was the other issue. I made a mistake and my DEF tank was full so after 18 months I decided I needed to exchange the DEF. Sadly there is no drain plug but I was able to disconnect the fill line and after an hour or so of tinkering I was able to siphon out virtually all of the old DEF.

I spent a lot of time with online research on this issue. If the warranty had not been a consideration I would not have even bothered with the oil change. Based on mileage and test results, 15,000 miles is very conservative. When condensation is not an issue, oil does not age at least over the period of a couple of years or so. Since I have been thoroughly warming up the engine that is not a concern either. I even wonder about water in the oil for short trips. How does water enter the system?

valhalla360 wrote:
Are those 50 miles all at once? Or is it 5-10 miles over several days?

If it's 50 miles all at once, the engine should get up to temp and stay there long enough to burn off any condensation (note: warming up an engine for a few minutes before an oil change is not the same thing and driving 5 miles would be similar).

I would probably go annual just so I don't forget entirely but even every couple years likely won't cause any issues. As mentioned, at 600miles per year, if the engine only lasts another 12000miles, that's another 20 years.

This is a good question, just a few miles operation per run is not going to be long enough to develop the heat in the oil to drive out any moisture present in the oil.

This is from experience, my DD work commute is 11 miles round trip.. Have always fought with moisture condensing on the oil filler cap creating a nasty milky sludge on the filler cap.. Gets far worse in winter than summer.. The only solution is to change the oil MORE OFTEN.

My own work commute was 100 mile round trip, never had an issue with moisture build up in the oil to create milky sludge..

Mex stated, oil gets to 120F when done, that is not enough heat to drive out the moisture and that will eventually lead to a build up of milky moisture laden sludge. Oil temp needs to get up to engine operating temps which is going to be closer to 200F for a period of time. Takes time and heat to drive out the moisture.

I would say better off to change oil at least within the manufacturers recommendations which is typically stated as miles OR MONTHS whichever comes first.

Back in the 70's that was typically 3,000 miles OR THREE MONTHS whichever came first. Wasn't until the early 2000s when manufacturers relaxed that recommendation.. Now days my 2020 is 10K miles or ONE YEAR, whichever comes first..

Oil changes are cheap compared to repowering a vehicle, a rebuilt block for OPs vehicle would cost more than 4 times what the vehicle is worth..

Brings me up to..

wa8yxm writes "Gas or Diesel?
The reason I ask if that Gas engines oil changes tend to be around 65 dollars at most of the shops I visit"

Guess you are in Cali or "New England" states.. You are getting ripped of big time.. Around my area passenger cars are no more than $30 at quick change places.. I do my own changes so it is oil and filter.. $4 for filter and $3.99 per quart x 7 quarts for $31.93 for my 6.2 gas engine..

Diesels often take 15 quarts and filter may be more, so at a min shouldn't be much more than $70 if you DIY..

covered wagon "That's what I saw too on an Onan that the Lady neglected to have changed for 2 1/2 years. I would pull the dip stick and be clear and nice. After you warmed it up for the oil change it was black and not nice oil. All she said was well... ''I never hardly ever used the generator''. So why do I need to have it changed?

I showed her the oil taken out in a clear pan and the bottom was starting to settle and looking milky. Not pretty.
"

theoldwizard writes "As long as it gets hot enough every month or so to drive out any condensation."

^^^THIS^^^

Yep, even though the OPs oil will not be "worn out" it WILL eventually get "moisture contamination" well before the oil has worn out.

OP has mentioned in the past being near the ocean for periods of time, that also can play havoc with contaminating the oil..

In this case, you should change the oil on a schedule based on the vehicles manufacturers recommendation in TIME rather than miles..

I would think OP would be fine to just change every 6 months or every year. Sort of depends on which works best for your memory AND location..

Use synthetic oil. You can go a long time on it. I like to change it after about 1 1/2 -2 years even if the mileage is low.

As long as it gets hot enough every month or so to drive out any condensation.

I have a Jeep Rubicon that gets driven roughly 1000K per year.
Change the oil after Christmas every year and run non ethanol fuel.

It's also a good idea to keep the fuel tank full to prevent rust.

Are those 50 miles all at once? Or is it 5-10 miles over several days?

If it's 50 miles all at once, the engine should get up to temp and stay there long enough to burn off any condensation (note: warming up an engine for a few minutes before an oil change is not the same thing and driving 5 miles would be similar).

I would probably go annual just so I don't forget entirely but even every couple years likely won't cause any issues. As mentioned, at 600miles per year, if the engine only lasts another 12000miles, that's another 20 years.

Gjac wrote:
I went several years before changing my genset oil because I only put 10 or 12 hrs a year on it. The dipstick was always clean and the level was good. When I did change it there was a lot of white creamy sludge in the bottom that did not show up on the dip stick. So condensation is a real problem especially over the winter, and even though I ran the genset before I drained the oil it did not burn off all that sludge. I don't know what an oil analyses would cost but I am sure it is more than my oil change and filter. I am sure there are a lot of variables as to were you live how long the engine sits between use etc, but I think a yearly oil change or every 12,000 miles is good advice.

That's what I saw too on an Onan that the Lady neglected to have changed for 2 1/2 years. I would pull the dip stick and be clear and nice. After you warmed it up for the oil change it was black and not nice oil. All she said was well... ''I never hardly ever used the generator''. So why do I need to have it changed?

I showed her the oil taken out in a clear pan and the bottom was starting to settle and looking milky. Not pretty.