Does oil weight/type get effected by E85?

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I just had an "oh yea" moment and forgot to mention that my car runs E85 a decent bit. You guys talked me into running Mobil 1 0W-40 European formula but none of you knew this detail.

So does E85 effect anything to do with what type oil should be used?
 
I just had an "oh yea" moment and forgot to mention that my car runs E85 a decent bit. You guys talked me into running Mobil 1 0W-40 European formula but none of you knew this detail.

So does E85 effect anything to do with what type oil should be used?
It is too thin for E85 IMO.
0W40 is exceptional oil, I ran it on track numerous times, but E85, something thicker or more shear stable. Personally, M1 5W50 or something like HPL BAS 5W40.
 
I just had an "oh yea" moment and forgot to mention that my car runs E85 a decent bit. You guys talked me into running Mobil 1 0W-40 European formula but none of you knew this detail.

So does E85 effect anything to do with what type oil should be used?
I would answer this another asking if the vehicle in question has direct fuel injection. If it does, then yes I agree.....0w40 is too thin. If it has port injection then 0w40 is probably ok. Direct injection engines have higher fuel oil dilution charecteristics IMHO.
 
I would answer this another asking if the vehicle in question has direct fuel injection. If it does, then yes I agree.....0w40 is too thin. If it has port injection then 0w40 is probably ok. Direct injection engines have higher fuel oil dilution charecteristics IMHO.
It's port injection and the PCV is vented to the atmosphere so no oil will get into the intake tract.
 
Then I think you will be ok. E85 does a great job of keeping valves clean, but you have to keep an eye on seals in the fuel system, and dont over fill the fuel tank where the evap cannister can get saturated.

I didn't know you couldn't over fill the fuel tank, that is good to know.
 
It's port injection and the PCV is vented to the atmosphere so no oil will get into the intake tract.
Still, it does not mean it will not get into oil.
Alcohol is a very effective diluter. So, you want something thicker.
Whatever you decide, do UOA to see where you at with KV100.
 
Still, it does not mean it will not get into oil.
Alcohol is a very effective diluter. So, you want something thicker.
Whatever you decide, do UOA to see where you at with KV100.

Yea I understand that. But I'm new so I don't know you guys' abbreviations. UOA and KV100?
 
It depends on how the engine is used. If the engine's sole purpose is drag racing, with low engine temps, then an oil catered to the fuel/water dilution is preferred. The same for an engine that's short-tripped, especially in winter. If the engine is used on the street or oval/road track, with sustained time @ >175°F (ethanol's boiling point), nothing special is needed.
 
It depends on how the engine is used. If the engine's sole purpose is drag racing, with low engine temps, then an oil catered to the fuel/water dilution is preferred. The same for an engine that's short-tripped, especially in winter. If the engine is used on the street or oval/road track, with sustained time @ >175°F (ethanol's boiling point), nothing special is needed.

It's a street car with roll racing sometimes. And it is rarely driven without getting up to operating temperature before shutdown.
 
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It's a street car with roll racing sometimes. And it is rarely driven without getting up to operating temperature before shutdown.

In that case, there's nothing special needed for the E85. Just make a routine of visual observation for signs of dilution (ie: milking).
 
One data point - the Tundra with the Flex Fuel engine has half the Oil Change Interval of the gasoline-only version.

Regular Tundra - 10,000 miles.

Flex Fuel - 5,000 miles.

Both of those are cut in half for severe service, by the way, so with Flex Fuel, in severe service, 2,500.

So, I think this is less about the oil, perhaps, and more about how often it gets changed.
 
OEM recommendations assume a worst case scenario for CYA. If you're not short tripping in 0°F weather with cheap conventional oil, I wouldn't worry too much about it. Note, that's not to say dismiss the recommendations entirely. I'm saying approach them with the mindset of the warranty department glazing those recommendations before publishing.
 
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