[Redline_2ss]

So I got tuned for flex fuel today and my tuner said they recommended an oil change every 3k miles. She said she recommends royal purple. I didnt get a chance to ask her but would the new mobil 1 esp 0-40 formula work also? If anyone else has flex fuel on their car what oil have you been using?

[TJay74]

There is zero reason to change your oil every 3k miles unless you just want to throw your money away. I wouldnt change the oil until 5k miles at the soonest, or go off of when the OLM monitor says it is time.

I change mine in the 5k-7.5k range and have for almost 15 years now.

[BlueinTN]

Originally Posted by TJay74

There is zero reason to change your oil every 3k miles unless you just want to throw your money away. I wouldnt change the oil until 5k miles at the soonest, or go off of when the OLM monitor says it is time.

I change mine in the 5k-7.5k range and have for almost 15 years now.

You ran E 85 for 15 years?


I think I ran one car for 9 now I change the oil pretty often but I also run conventional oil since moisture mixes with it. Synthetic oil doesnt mix with water so they must be worried about moisture in the oil.



All the cars I have its hard to get the operating temp up with E 85.

[6spdhyperblue]

With a 174+ stat have no issues getting the oil temp enough to cook off the water on E

[TJay74]

Originally Posted by 6spdhyperblue

With a 174+ stat have no issues getting the oil temp enough to cook off the water on E

Same here, I run a 160° stat with zero issues.

So now explain to me this, how in the heck is "moisture" getting into your oil from burning E85? Unless you are pouring pure E85 into your oil you shouldnt have any moisture in your oil. And before you tell me E85 absorbs moisture, I know that but it isnt like it absorbs ounces to gallons of it each tank. I highly doubt for someone who runs a tank of E85 out every week that you would be able to tell a difference in the moisture content of the E85.

There is a very slight, and I mean slight amount of unburnt E85 that makes it out of the combustion process, and even then a even more slight percent of that unburnt E85 might make it past the ring lands into the oil system.

You are making a mountain out of an ant pile. Change the oil every 5k or when the OLM tells you to, otherwise throw your money away and change it every month or 3k.

I have ran full synthetic and E85 for several years now, zero issues.

[Redline_2ss]

Thanks guys! I was super confused when they told me to do oil changes so often. I already do them every 5k miles and it didnt make sense to me. Just wanted to see if anybody else was having any issues with e85 and oil changes

[driven2exceSS]

Just so it is said... If you Track the car (which you may not by the sounds of it) the intervals will change from the recommended: "Change the oil every 5k or when the OLM tells you to", otherwise stick to this and carry on, and change at least once a year.

[Booher]

From what I know. E85 loves moisture, so it's good to put an additive in your tank every now and then. When running e85, your oil life is cut in half, that's why they recommened the oil change. Try not to leave it in your gas tank for too long, (like a couple months) as it will pull moisture out of the air and begin to separate, which is bad. Most newer cars can handle e85 with a tune and flex fuel kit, but older cars, it degraded the fuel lines. I'm guessing because it's more corrosive. Everyone should research e85 before they get it installed imo, so you don't mess anything up. Dont take one or two persons advice, read up , and take it as a collective whole.

[6spdhyperblue]

What do the manuals of the 2014+ flex fuel silverado 1500 say to do differently when running flex fuel?

[Rlhay2]

With E85 you are jamming 30% more fuel into the compression chamber. Every cylinder has some leakage, thus this extra fuel winds up in the oil.


The E85 contaminated oil is OBVIOUS at as little as 1500 miles. On a stock car, it may not have any adverse affects to run that oil for another 3500 miles. On my 850rwhp car, I change the oil every 1500-2000 miles.

And I wouldn't run 0-40 oil in a warm climate.

[BlueinTN]

Originally Posted by 6spdhyperblue

With a 174+ stat have no issues getting the oil temp enough to cook off the water on E

Its 94 degrees today box stock 2018 Zl1 1le i never saw my oil temp go over 200...yeah its the stock micky mouse guage...but I keep it up all day and was the only gauge I watched.

[KingLT1]

E85 won't hurt anything. You will have to change the oil sooner and the OLM will reflect it. Other then that let it eat.

[6spdhyperblue]

Originally Posted by Rlhay2

With E85 you are jamming 30% more fuel into the compression chamber. Every cylinder has some leakage, thus this extra fuel winds up in the oil.


The E85 contaminated oil is OBVIOUS at as little as 1500 miles. On a stock car, it may not have any adverse affects to run that oil for another 3500 miles. On my 850rwhp car, I change the oil every 1500-2000 miles.

And I wouldn't run 0-40 oil in a warm climate.

Do you have ported heads?

[BlueinTN]

Originally Posted by Redline_2ss

So I got tuned for flex fuel today and my tuner said they recommended an oil change every 3k miles. She said she recommends royal purple. I didnt get a chance to ask her but would the new mobil 1 esp 0-40 formula work also? If anyone else has flex fuel on their car what oil have you been using?

If you are worried about it I would pull an oil sample and see whats what.