Wasn't sure what forum to post this in since two of the 4 engines can currently run E85, so I thought I'd post it here.

Are there any concerns with running E85, other than the need for more frequent oil changes (not sure why that is, but I read it somewhere).

Is there a noticeable difference in performance (better/worse)? Performance is defined as power & MPGs in this case. In other words, does the truck feel more sluggish or powerful, and is there any impact to MPGs for the same driving habits for E85 vs unleaded?

This is just part of my decision process for EB vs 5.0. Trying to figure out if there's much value in the fact that you can run E85 in the 5.0 and not the EB.

Thank you

 

I had an 07 E85, it will run cleaner and a little more efficient on the E85, thus cleaning the engine more which will dirty up the oil quicker. MPG's will only be slightly better. Haven't payed attention lately, but in 07 I made a trip from Pittsburgh Pa to Clearwater Fl. approx 1170 miles and only found 2 stations that sold it! Never bought another one. I would have to say the best value is in the EB, that's why I bought one!

 

E85 will give you slightly more power, but you get about ~66% of the fuel mileage that you get with regular gas (E10). The difference in cost for E85 in my area, plus the extra maintenance costs, doesn't cover the drop in mileage.

 

Assume you mean regular gasoline MPG will be better than E85.

Drivability, NVH, and other attributes are not notably different when using the alcohol-blended fuels. The higher octane of alcohol-blended fuels allows a small increase in power and performance (approximately 4%), but this is offset by the lower fuel economy (approximately 33%) due to the lower energy content. Cold starts with alcohol-blended fuels are somewhat more difficult than with gasoline due to the lower volatility of alcohol-blended fuels; 10% vaporization occurs at approximately 100 °F for gasoline vs. 160 °F for 85% ethanol. Ethanol requires approximately 37% more flow than gasoline due to a lower heating value (29.7 vs. 47.3 MJ/kg). Consequently, Flex Fuel vehicles require higher flow injectors than their gasoline counterparts. This results in a smaller fuel pulse widths with gasoline and makes the task of purging the canister more difficult during idles and decels.

In order to maintain proper fuel control, the PCM strategy needs to know the stoichiometric Air/Fuel Ratio for use in the fuel pulse width equation. On pre-2000 MY flex fuel vehicles, the percent alcohol in the fuel was determined by reading the output of the Flex fuel Sensor. The percent alcohol was stored in a register called Percent Methanol (PM). Although current alcohol-blended fuels only include ethanol, the percent methanol nomenclature has persisted. On 2000 MY and later vehicles, the Flex Fuel Sensor has been deleted and PM is inferred. The strategy to infer the correct A/F Ratio (AFR) relies on the oxygen sensor input to maintain stoichiometry after vehicle refueling occurs. The relationship between PM and AFR is shown in the table below.

Stoich Air Fuel Ratio = 14.64 - 5.64 * PM
PM (percent alcohol) Stoichiometric AFR
0.00 (100 % gasoline) 14.64
0.05 14.36
0.10 (standard gasoline) 14.08
0.15 13.79
0.20 13.51
0.25 13.23
0.30 12.95
0.35 12.67
0.40 12.38
0.45 12.10
0.50 11.82
0.55 11.54
0.60 11.26
0.65 10.97
0.70 10.69
0.75 10.41
0.80 10.13
0.85 (standard E85) 9.85
0.90 9.56
0.95 9.28
1.00 (100% ethanol) 9.00

 

Everything you ever wanted to know about E85...

E85 | The Truth About Cars

 

Leave the corn for eating, not an inefficient fuel!!! That is all.

 

(Assume you mean regular gasoline MPG will be better than E85.)
Yea If I remember correctly I think it got better mpg's on reg. gas than on the E85, but the motor seemed to perform better on the E85. I dont know its been too long and when I had it I only ran 3-4 tanks of E85, had to go to far to get it! I think the E85 was cheaper to buy also, maybe!

 

Ditto, would never put E85 in my tank. The mileage is terrible and the alcohol attracts water. It's bad enough that I have to run 10% alcohol gas. There is only one Mobil station in my area that sells the E85 and even at a 40 cent per gallon discount, you hardly ever see anyone pulling up to this pump. Running alcohol gas is the worst idea ever hatched.

 

I would never put E85 in my truck. Another dumb Washington idea.

 

if i had access to E85 on a daily basis, i would use it. I put it in my truck a couple of times and could really tell the difference in performance.

But, I would do it because we are being held hostage by the oil companies, and we will never get out of this oil dependent "rut" we are in if we don't develop energy sources to help the cause.

 

Thanks for running up food prices.