2015 E85

Northside · June 27, 2015

Ugh why would you willingly put that crap in your vehicle? It was supposed to be cheaper to offset the lower MPG but now it's about the same price so it's just a total lose-lose.

http://www.edmunds.com/fuel-economy/e85-vs-gasoline-comparison-test.html

Well some of us like the improved performance. I find most guys who call it crap and generally badmouth E-85 have never run it in a '14-'15 GM truck. I see you post that you drive a Toyota. A lot of us have run it and like it. It's free horsepower. Even if it cost a bit more per mile a lot of us would still run it for the increase in power.

JRaschke11 · June 27, 2015

Well some of us like the improved performance. I find most guys who call it crap and generally badmouth E-85 have never run it in a '14-'15 GM truck. I see you post that you drive a Toyota. A lot of us have run it and like it. It's free horsepower. Even if it cost a bit more per mile a lot of us would still run it for the increase in power.

My 2015 Denali will be waiting for me when I move back to the states. I drive a little Toyota car in Japan but if I could drive a truck I would for sure. I ordered the 6.2 and I don't think they make them flex fuel. I admit I haven't run it in a newer vehicle, but my hatred for ethanol lies in how corrosive it is and all the damage it has done to the fuel systems of family and friends' vehicles.

Higgs Boson · June 27, 2015

You guys are getting gas cheap. I just filled up for 3.00

Ethanol is 1.85 and 93 is 2.99

Northside · June 27, 2015

My 2015 Denali will be waiting for me when I move back to the states. I drive a little Toyota car in Japan but if I could drive a truck I would for sure. I ordered the 6.2 and I don't think they make them flex fuel. I admit I haven't run it in a newer vehicle, but my hatred for ethanol lies in how corrosive it is and all the damage it has done to the fuel systems of family and friends' vehicles.

The thread is about E-85 in 2015 trucks. You ordered a 6.2 in your Denali. That's great and it won't be E-85 capable so it won't be an issue for you. I've heard all the horror stories about ethanol, but never really saw any damage from ethanol, other than it hurt gas mileage a bit. I live in a dry climate so maybe that has something to do with it. That's still not E-85, the horror stories are about E-10 and the fear of E-15. E-85 only for flex fuel vehicles which are designed to handle the stuff.

I have run E-85 exclusively in my '14 Silverado 5.3 for about 18 months. It runs like a bear, way more responsive than on 91 octane. The fuel system was designed to run on this stuff so no corrosion problems. The engine has 11:1 compression. Compression will detonate even 91 or 93 octane gas unless the timing is retarded and power is reduced. E-85 is over 100 octane and will allow more advanced timing which allows the engine to produce the power it's capable of. My truck is so much more fun to drive on E-85 because of the instant throttle response and all around snappier performance. I'd have gotten a 6.2 in my truck but they were rare as hen's teeth in November of '13, so I run E-85, and have the power I like.

Fuel that does that is not crap! Too bad that the 6.2s with 11.5:1 compression aren't set up for E-85. They'd benefit even more from it.

rocknfire · June 27, 2015

The owners manual says there is no reason to run the tank low when switching to e85 because there is a sensor that reads alcohol content and adjusts the tune.

Higgs Boson · June 27, 2015

The owners manual says there is no reason to run the tank low when switching to e85 because there is a sensor that reads alcohol content and adjusts the tune.

depends on the model year of the truck. in some, the "sensor" is virtual, which means it uses fuel trim errors to determine what is in the tank (assuming the vehicle is either stock or properly tuned). It works pretty good, just slower than a physical sensor.

bigsapper · June 27, 2015

The owners manual says there is no reason to run the tank low when switching to e85 because there is a sensor that reads alcohol content and adjusts the tune.

You'll dilute the alcohol content if you don't run it to almost completely empty before switching.

rocknfire · June 27, 2015

That's why there is a sensor. Full effect is usually felt after 2 tanks once you get all e85 in there. 14's and 15's have the sensor.

bigsapper · June 27, 2015

I get that. The point is, the closer to absolute empty you go the less dilution.

I just ran a tank of 93Oct to get re-tuned for gas. I ran as close to empty as possible before re-filling with E85. My pump typically reads 80% actual; right now it's at 75% and I have racing today.

Higgs Boson · June 27, 2015

75 vs 80 is not going to change your life.

joshc64311 · June 28, 2015

I found a part number for the flex fuel sensor, GM OEM Part Number 13577429 GM Fuel Composition Flex Fuel Sensor. I have read that there is a plug for it in between the fuel tank and the back of the transmission on the driver side frame rail and from what ive read the fuel tables are already on the ecm. I wonder if I were to get this sensor would the ecm recognize it or would I have to unlock the tables?

bigsapper · June 28, 2015

The plug for the sensor should already be in the wiring harness. You'll need to unlock the tables in the ECM.

joshc64311 · June 28, 2015

how would I go about doing that

Higgs Boson · June 29, 2015

it's not really unlocking anything, it's basically just enabling the sensor.

TxTruckMan · June 29, 2015

I bet this has to do with the new gas regulations kicking in. Previously, OEMs were given CAFE credits for things like FlexFuel. The problem is that not many people use it or have access to it, so it didn't really help save any gas consumption. I thought I read that with the new regulations kicking in for 2016, the credits for FlexFuel vehicles were going to be removed. Something like the OEMs had to verify that E85 was used to receive the credit? Anybody know more?