Originally Posted By: gaijinnv
Originally Posted By: -SyN-
I have read and seen pics of tore down engines in testing showing Very clean Valves and The tops of pistons being very clean while running Ethanol Fuel--E10 or whatever is at the pumps...
Is this maybe the only benefit to Ethanol fuels?
Though I have read where Ethanol fuels will not really clean carbon it will keep a new motor clear of carbon build up...
What are your thoughts... Within my new Ram I have only seen so far a MPG change from filling up with E10 or whatever is actually in their tanks... 100%Gas=22.1 mpg highway with E10=17.8 mpg highway...
If the Ethanol will keep the Valves and Pistons clean I see no use for fuel system cleaner... If It is keeping these clean I assume it is doing the same with the injectors.
I do add 1oz per 5gal of TC-W3 every fill up as well...
In the case of the Toyota Flex-Fuel (up to E85) 5.7L 3UR-FBE engines, instead of the 10,000 mile OCI recommended for the E10 version of the engine a 5,000 mile OCI is recommended.
Further, if E85 is used (higher Ethanol content) the OCI becomes only 2,500 miles.
This indicates to me that at least Toyota thinks the higher Ethanol blends make engine oil dirtier.
To wit:
*The 2TR-FE (4Runner / Tacoma) and the 3UR-FBE (Flex Fuel Tundra / Sequoia) are the exceptions to this new change interval program; these engines have not been approved for the 10,000 mile interval at this time. A 5,000-mile/6-month oil change interval is still required for these vehicles. Also, the Flex Fuel 3UR-FBE requires a 2,500 mile interval when operated on E85.
See source material here:
Toyota OCI FAQ
HTH
I am not sure they think it makes engine oils "dirtier" as much as they are concerned about increased water contamination in the oil. There is enough evidence to suggest that water contamination is an issue in the engine oil with higher levels of ethanol use. This is one of the issues that the oil brand I chose actually makes it a point to formulate for higher ethanol use in engines, to address those potential problems. Since I generally use blend of between E15 and E85, I specifically wanted an oil in the engine that made it a point to at least claim that one of it's major benefits was to address issues with higher ethanol blends. As much as the dexos1 thing seems to be gospel to some folks, it is rather a weak standard in dealing with higher levels of ethanol usage, which seems bizarre given that GM is so pushing the flex fuel thing.
Regarding the OCI of an engine using higher blends of ethanol. I see no major interval change on the OLM of my 2013 Silverado whether it is using E10 or E85. And it sure can tell the difference in the calculation of that. Toyota may have its own reasoning. For many folks ti doesn't matter, as they usually change the oil by 5000 miles anyway. Most consumers are not members of forums such as this one.