Oil changes with synthetic

[pasusan]

How often do you change your oil if you use full synthetic oil?

We have a Chevy 6.0 gasoline engine. We are putting Mobil 1 synthetic oil into it and are finding differing requirements. Some say go by miles, others say if you don't put on that many miles change it every year.

We only drive it 2000 to 3000 miles per year. Can we really wait for 7000 miles or more to change it or should it be done every year?

My thinking is why go synthetic if you have to do it every year anyway?

[Cummins12V98]

"I agree, oil gets beat up pretty bad when towing."

100% disagree.

I will take my Cummins engine that has 1/2 of it's miles towing WestCoast at 35k combined with 93k over the same engine same miles that has been a local stop n go with a bit of freeway miles any day!!

[jerem0621]

mosseater wrote:
Many years ago, when Hector was still a pup, and folks still believed in silly things like objectivity, Consumer Reports did a pretty thorough test with NY city taxi cabs and oil changes. Sythetic was still a niche market then, but after running taxis for 100K miles on almost all readily available oil brands, they tore them down to inspect and measure. The conclusion was, as long as the oil was changed at the then-standard 3000 miles, it didn't matter if it was mobile one or PepBoys reclaimed oil. Their conclusion was to make sure you changed it. Take that info for what you paid for it.
That said, two things to keep in mind: Your truck may have an "extreme duty" PM schedule because you tow or haul (Ford dealer service manager told me even if you tow occasionally). Point two...I have zero doubt oil now is better than its ever been, so I have confidence that it's lubrication capabilities are up to the 5 or 10K mile task. But....that black stuff in oil, that makes it black? That's dirt. It aint food coloring. Contaminants are so named because they aren't supposed to be there. I have historically changed mine in my former sig pic F 150 because I ran the dog pee out of it when towing. It never went past 4000 miles without a change. For the cost of Motorcraft synthetic blend and a new filter, I'll eat the minimal cost difference to keep sleeping soundly at night with the new truck as well. When my odometer in my 7.3 gas engine in my new F-250 hits about 4000 miles, I'll be crawling under it again with my drain pan. Thats my 4 cents. Y'all can do as you wish. The cost of one oil change per year wouldn't make most of us even blink. I'd love to be in that club.

I Will be doing he exact same with my brand new 2022 Chevy. It's a turbo truck and I will be changing he oil at 4,000 mile intervals or when the OLM hit's 50%, whichever is first.

Oil is cheap, engine work is NOT.

Thanks!

Jeremiah

[dodge_guy]

mosseater wrote:
Many years ago, when Hector was still a pup, and folks still believed in silly things like objectivity, Consumer Reports did a pretty thorough test with NY city taxi cabs and oil changes. Sythetic was still a niche market then, but after running taxis for 100K miles on almost all readily available oil brands, they tore them down to inspect and measure. The conclusion was, as long as the oil was changed at the then-standard 3000 miles, it didn't matter if it was mobile one or PepBoys reclaimed oil. Their conclusion was to make sure you changed it. Take that info for what you paid for it.
That said, two things to keep in mind: Your truck may have an "extreme duty" PM schedule because you tow or haul (Ford dealer service manager told me even if you tow occasionally). Point two...I have zero doubt oil now is better than its ever been, so I have confidence that it's lubrication capabilities are up to the 5 or 10K mile task. But....that black stuff in oil, that makes it black? That's dirt. It aint food coloring. Contaminants are so named because they aren't supposed to be there. I have historically changed mine in my former sig pic F 150 because I ran the dog pee out of it when towing. It never went past 4000 miles without a change. For the cost of Motorcraft synthetic blend and a new filter, I'll eat the minimal cost difference to keep sleeping soundly at night with the new truck as well. When my odometer in my 7.3 gas engine in my new F-250 hits about 4000 miles, I'll be crawling under it again with my drain pan. Thats my 4 cents. Y'all can do as you wish. The cost of one oil change per year wouldn't make most of us even blink. I'd love to be in that club.

I agree, oil gets beat up pretty bad when towing.

Think about all the heat cycles and pressure it’s put through next time you’re climbing I70 in CO or any big climb!
And with that…..how many people change their transmission fluid regularly. I do my trans every 25-30k miles. When I had the Excursion even the rear diff got new fluid at the same intervals.

I also wonder how many people replace their brake fluid? This is a safety item and when towing (stopping) brake fluid gets very hot! Here again I change the fluid at every brake job, about 30-40k miles. On my class A it gets done about every 3 years.

[fj12ryder]

Actually, especially with a diesel, that black color isn't dirt. And if your oil isn't changing color, it's not doing it's job of keeping "dirt" in suspension like it's supposed to. If I went by color I'd be changing the oil in my Cummins after 1,000 miles. Mostly "Old Mechanic's Tale". 🙂

And it would have been interesting to see Consumer Reports results if they had done differing oil change intervals. Never been much of a fan of Consumer Reports anyway.

[mosseater]

Many years ago, when Hector was still a pup, and folks still believed in silly things like objectivity, Consumer Reports did a pretty thorough test with NY city taxi cabs and oil changes. Sythetic was still a niche market then, but after running taxis for 100K miles on almost all readily available oil brands, they tore them down to inspect and measure. The conclusion was, as long as the oil was changed at the then-standard 3000 miles, it didn't matter if it was mobile one or PepBoys reclaimed oil. Their conclusion was to make sure you changed it. Take that info for what you paid for it.
That said, two things to keep in mind: Your truck may have an "extreme duty" PM schedule because you tow or haul (Ford dealer service manager told me even if you tow occasionally). Point two...I have zero doubt oil now is better than its ever been, so I have confidence that it's lubrication capabilities are up to the 5 or 10K mile task. But....that black stuff in oil, that makes it black? That's dirt. It aint food coloring. Contaminants are so named because they aren't supposed to be there. I have historically changed mine in my former sig pic F 150 because I ran the dog pee out of it when towing. It never went past 4000 miles without a change. For the cost of Motorcraft synthetic blend and a new filter, I'll eat the minimal cost difference to keep sleeping soundly at night with the new truck as well. When my odometer in my 7.3 gas engine in my new F-250 hits about 4000 miles, I'll be crawling under it again with my drain pan. Thats my 4 cents. Y'all can do as you wish. The cost of one oil change per year wouldn't make most of us even blink. I'd love to be in that club.

[specta]

Changing the cars oil every 5000 miles means it gets changed about every 3 months.

Right now changing the trucks oil every 5000 miles means it gets changed about every 5 months. The truck gets driven every week.

My truck with the camper loaded weighs 10850 pounds. I've only had the camper off the truck once in over a year and it was only for two days when I took a car trailer to SLC to get a car for a friend.

The truck gets worked pretty hard every time it gets driven. No way am I going to scrimp on oil changes. Besides, I do them myself so its not a huge expense.

And I rotate the tires every oil change too.

[specta]

Cummins12V98 wrote:
"No way could I go a full year without an oil change. I just couldn't do it."


The oil Companies love you.

I'll bet they do. LOL

[dodge_guy]

I have seen my share of sludged up or damaged motors from lack of oil changes! I e yet to do a motor on something that was properly maintained!

[StirCrazy]

I use full synthetic , but I do not ue it to extend my oil chang intervals. when the truck tells me to change it I change it weather its once or twice a year. I switched to synthetic for the antishear properties under elevated heat and presure. living in a semi arid climate, in the middle of mountians I do a lot of long pulls in hot temps.

Steve

[Huntindog]

The big difference in synthetic vs. dino is that synthetic can take much higher tempertures. This is important for certain motors. If your motor doesn't need high temperture oil, then there really is no reason to use synthetic. Dino oil doesn't wear out. It gets contaminated and diluted, just like synthetic does. That is why oil needs to be changed, no matter which type you use.

I tried sythetic once That motor had numerous oil leaks. Could have been a coincidence... But synthetic does pour like water, so it makes sense that it could get by seals easier. Which brings up cold weather performance. In VERY cold temps, it should do better.But I don't think it gets cold enough in the lower 48 to matter.

[Lantley]

I would contend oil problems come from ignoring the oil period.
Be it low oil, dirty oil or no oil.
To your point if one is at least attempting to pay attention to their oil, they will be OK.
When to change oil is less of a factor.

[time2roll]

Oil problems happen from running low on the oil level not from extended change intervals with quality oil and filter.

[Lantley]

Maybe not you guys but I'm not naive enough to believe, everyone changes their oil on time and technicians never see any oil issues.

[ktmrfs]

dodge guy wrote:

Cummins12V98 wrote:
"No way could I go a full year without an oil change. I just couldn't do it."


The oil Companies love you.

And technicians love the extended oil change guys!

Lets see:
1995 S-10 250K miles changed oil every 7500, still isn't using any oil
2004 Duramax just turned 260K miles, changed oil at 10% life or so, 8-10K miles uses about 1/2 qt/10K miles, same as at 10K miles
1987 Chevy van, 195K miles, changed oil every 7500 miles, used maybe 1/2qt
1997 Honda accord, 160K miles, changed oil with oil change light, still wasn't using oil

And on all the vehicles used specified oil, usually not full synthetic, Blackstone labs results always came back with oil with good TBN and typical other indicates at the extended oil change interval.

Why would I use any other change interval????????????

[time2roll]

dodge guy wrote:

Cummins12V98 wrote:
"No way could I go a full year without an oil change. I just couldn't do it."


The oil Companies love you.

And technicians love the extended oil change guys!

I have been in virtually never in 21 years. Must really love me 😉