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E85 Flex Fuel Do you run it yes or no

E85 Flex Fuel


  • Total voters
    9
  • Poll closed .

Mr.G

Full Member
Joined
Feb 29, 2020
Messages
61
Location
Northern California
I just want to see how many of us 2007 newer 5.3L Flex owners Still run the E85 Flex fuel or not, and hears why.

Last year when I had my 07 at the Dealer for repairs, they told me not to run Flex fuel because it was bad for the engine even though the engine was designed and built to run E85 flex it was bad for it.

But now that in my area regular gas is up pass $6.00 a gallon and E85 is almost $2.00 cheaper I was thanking about when I'm near the only station in my area that has it to fill up with it.

I was reading on the station's web site that the average octane for E85 is 100 to 105.
 
There has been tons of threads dealing with ethanol in gas and it's bad side effects already discussed. I don't see the long term economy if it screws up the motor, lessens miles per gallon and spoils quicker if you let it sit. Greater need for fuel stabilizer to ward off gas decay etc.
 
Calculate your cost per mile driven to determine which fuel to use.

Your "Dealer" making that statement would be enough for me to seek any future service elsewhere.

But, I only visit dealer service departments for factory recall work and luckily those are few and far between.
 
yeah I would move... $2 more then I pay here
 
I heard on news that these gas stations in California can charge as much as long as theres no state of emergency. Get the !!?? Out of California.
We are looking, elsewhere, we moved back to California 20 years ago when my wife's dad had a stroke, he passed this last February and now we have been talking about looking at leaving.
 
I just want to see how many of us 2007 newer 5.3L Flex owners Still run the E85 Flex fuel or not, and hears why.

Last year when I had my 07 at the Dealer for repairs, they told me not to run Flex fuel because it was bad for the engine even though the engine was designed and built to run E85 flex it was bad for it.

But now that in my area regular gas is up pass $6.00 a gallon and E85 is almost $2.00 cheaper I was thanking about when I'm near the only station in my area that has it to fill up with it.

I was reading on the station's web site that the average octane for E85 is 100 to 105.
I run E85 in my 07 ltz every now and then it's about a $1 cheaper here in Colorado my Avalanche runs good on it I haven't had any issues so far
 
I run E85 in my 07 ltz every now and then it's about a $1 cheaper here in Colorado my Avalanche runs good on it I haven't had any issues so far
Good to hear, we're heading that way today on an 3 week Vacation, Oldest Grandson graduating High School, and my Granddaughter turning 16 this month, so this run East also gets to see how the new intake works out, (see Picture) A CARB compliant Volant Performance intake.

Thanks for letting us know what you use.

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I recently started using E85 gas being much cheaper now in so California. 3.99gal compare to 6.5 average regular gas. Was ok when mixed with regular stuff, after a few fills only e85 tried towing trailer short trip to empty Black tank.
Barely pulled trailer considerable power loss. Then later on the catalytic converter bank 2 engine light came on. Degradation performance bank 2 CAT.
Going to switch back to premium unfortunately & put a fuel/CAT cleaner treatment in gas Tank.
Reset trouble codes will see if CAT problem cleans out or not.
If not will try removing & cleaning CATs b4 replacement.
Anyone else get dirty CAT after running e85?
 
Never have and probably never will. It seems (like above) there is too often some issue noticed when it is used along with the known negative issues. Most of the miles driven these days are put on pulling the tear drop somewhere, although not often enough. Running some errands etc. doesn't burn that much fuel so I can justify normal gas yet. I check for stations with 100% gasoline on this Pure Gas app if I need gas further from home where it is available, but it is usually too far out of my way to make it worth it and it does cost a little more.
 
I recently started using E85 gas being much cheaper now in so California. 3.99gal compare to 6.5 average regular gas. Was ok when mixed with regular stuff, after a few fills only e85 tried towing trailer short trip to empty Black tank.
Barely pulled trailer considerable power loss. Then later on the catalytic converter bank 2 engine light came on. Degradation performance bank 2 CAT.
Going to switch back to premium unfortunately & put a fuel/CAT cleaner treatment in gas Tank.
Reset trouble codes will see if CAT problem cleans out or not.
If not will try removing & cleaning CATs b4 replacement.
Anyone else get dirty CAT after running e85?
Thanks for your input Wpolonavyguy;

These are the types of things we need to know,

I had always ran a mixture never ran a pure tank of E85, however I don't think that you are going to have to remove your CATs.
 
Only for about 2 months now. When the gas prices jumped about $1 in a month, I thought I'd give it a try
 
I’ve been running on E85 several times, depending the price. It works really nice. Actually prefer E85 before 95 octane.
 
I totally agree. And considering we're gassing up 3 vehicles right now, it makes it nice. Even my husband is running E85 in his.
 
We are running E85 $3.99 a gallon when regular unleaded $6.15 and so far we have not really noticed that much of a change in MPG running around town most of the driving has been under 60 and our mileage has been sitting at about 15 combined so I'm not going to piss and moan if they make me run E85 in my truck for now, because it has actually started running smoother because it does not have all the additives that are required by CARB here in California. So until something goes wrong with my truck I'm good for now running E85.
 
We are running E85 $3.99 a gallon when regular unleaded $6.15 and so far we have not really noticed that much of a change in MPG running around town most of the driving has been under 60 and our mileage has been sitting at about 15 combined so I'm not going to piss and moan if they make me run E85 in my truck for now, because it has actually started running smoother because it does not have all the additives that are required by CARB here in California. So until something goes wrong with my truck I'm good for now running E85.

Hopefully all will run and stay well for all of you using E85.

E85 scares me. I have a friend's brother that lives in CA. 2018 GMC 1500, low mileage, no issues. Started using E85 early this year and killed the motor. No saving, either had to replace motor or sell. Lucky for him, with the market the way it is, the dealership bought his truck for $29K with the blown motor. I think someone else in this forum mentioned the same result with his/her Avanlanche and was wondering if it was a coincidence--"there are no coincidences."
 
Interesting… I bought my Flex Fuel about a year 1/2 ago, started running flex about a 3 months later, no issues until 2 months ago, trans needed rebuilding and then last month the motor got a tic in it out of nowhere, and the came to find out the motor was terminal DOA. For an extra $300 I got a new 5.3 Flex Fuel motor and a 3 year unlimited mile unconditional guarantee. I‘m running flex in it now to test the legend of E85 possibly being an engine killer. So if it blows again, then we‘ll all know, and I’ll still get a new engine for free, and I’ll never run flex again, but if it doesn‘t then I’m good to keep using it.
 
The fuel CAT cleaner treatment & premium gas a bit the code never came back on. I may add 85 mixed with other gas try again see if cats get clogged again but definitely keeping eye on it.
The cats could need cleaning I'm not original owner but I do my best keeping vheicles maintained.
I clean everything when working on engine parts a ocd I got from classic car restoration with father & continue to my newer version cars & truck.
 
The fuel CAT cleaner treatment & premium gas a bit the code never came back on. I may add 85 mixed with other gas try again see if cats get clogged again but definitely keeping eye on it.
The cats could need cleaning I'm not original owner but I do my best keeping vheicles maintained.
I clean everything when working on engine parts a ocd I got from classic car restoration with father & continue to my newer version cars & truck.
Yes keep us updated on how things go, I run it off and on and have not noticed any issues, I am using the Torque app to keep an eye on things, have noticed a slight rise in exhaust temperature when running e85, cat temperature on right side especially.

Have read that you should re-tune these 5.3 to run the e85, since I have a programmer that I used for reprogramming tire size next time I run e85 I will re-tune to run and see what happens.
 
Ya I've invested quite a lot in past 6months luckily I don't drive it far usually just kids to & back school about a mile & towing trips with camper.
Believe I need a new torque converter as already put all new solenoids wiring & shift sensor plate? Forget technical name but temperature of fluid sensor built into it.
I'm looking into a good programmer to get soon as the stock program not very responsive. Monster transmission has converter I'm planning on installing and ill pay to get pressure plates & other transmission parts checked as to prevent any future failure.
I've come close to changing out all sensors & electronic parts getting close to new again.
Plan to keep this truck & customize as no payments finally owned outright.
 
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