Should I try running E85? Or stick with unleaded.

[swathdiver]

i live in NJ, theres not one station that sells e85. pretty dumb being Long Island is full of corn and it has to travel through NJ to get to LI lol

Well, I found one! A Power Gas in East Orange and they sure are proud of E85 @ $2.53 a gallon.

 

[Scottydoggs]

id be driving there, fill it up, then need another tank when i got home. ( not really that far away) but to far to be worth it. the key to e85 is it needs to be local.

thats a start tho. we grow the corn here, dont see why they dont sell it all over here, unless they need a new tank installed for it, then i could see none getting sold.

 

[Matahoe]

The issue with ethanol is not that it causes deposits...it actually burns very clean. The issue is that it attracts water. That in effect can cause corrosion of fuel components and buildup of deposits on pistons and valves.

 

[swathdiver]

...the key to e85 is it needs to be local.

There are other stations listed on other websites, places on Gas Buddy drop off if nobody reports fuel prices in 48 hours. Then you have areas where people just won't report E85 prices at a particular station. Look for yellow gas handles. I agree, it would be quite difficult to plan a trip to Texas from Florida and expect to run E85 all the way there and back. There's too few stations along the way and of course the distance between stops is less. Being diabetic, that isn't a problem!

The issue with ethanol is not that it causes deposits...it actually burns very clean. The issue is that it attracts water. That in effect can cause corrosion of fuel components and buildup of deposits on pistons and valves.

Let's explore this water angle. How so? Will my tank have several gallons of water in it after a time? After 18 months of on and off use I don't think that's the case. As for build up on the pistons and valves, Maybe I should stick a bore camera down a spark plug hole and have a look?

 

[SnowDrifter]

There are other stations listed on other websites, places on Gas Buddy drop off if nobody reports fuel prices in 48 hours. Then you have areas where people just won't report E85 prices at a particular station. Look for yellow gas handles. I agree, it would be quite difficult to plan a trip to Texas from Florida and expect to run E85 all the way there and back. There's too few stations along the way and of course the distance between stops is less. Being diabetic, that isn't a problem!



Let's explore this water angle. How so? Will my tank have several gallons of water in it after a time? After 18 months of on and off use I don't think that's the case. As for build up on the pistons and valves, Maybe I should stick a bore camera down a spark plug hole and have a look?

Edit: Researched response posted below

 

[adriver]

Where can I find my RPO codes? Are they still in the glovebox like they were back in the day? My gas cap is currently black but i have no idea if its original or not.

Your VIN and RPO code. The engine's look identical between the LM7 and L59 but you will have much larger fuel injectors and the rail might be different. I'm not familiar enough to tell. Also, yours has an alcohol content sensor and your original gas cap was yellow. If you have a good scan tool or fancy OBD adapter, you can view the alcohol content whereas a regular truck will not have that feature.

VIN # 8th digit
V 4.8
T 5.3
Z 5.3 FF
U 6.0 LQ4
N 6.0 LQ9

 

[chrmbly]

I never tried it, but I’m tempted in my 2014 Sierra. I always thought the lower mpg made it a negligible cost savings

 

[SnowDrifter]

I never tried it, but I’m tempted in my 2014 Sierra. I always thought the lower mpg made it a negligible cost savings

It depends on the cost of E85. Sometimes it's a saving, sometimes its not.

However, independent of cost, it might be worth running a few tanks of E85 back to back every few years. Ethanol is extremely clean burning and does a great job of cleaning up carbon left behind by E10 fuels.

This is after a 3k mile run of e85. Clean as a whistle!

 

[SnowDrifter]

There are other stations listed on other websites, places on Gas Buddy drop off if nobody reports fuel prices in 48 hours. Then you have areas where people just won't report E85 prices at a particular station. Look for yellow gas handles. I agree, it would be quite difficult to plan a trip to Texas from Florida and expect to run E85 all the way there and back. There's too few stations along the way and of course the distance between stops is less. Being diabetic, that isn't a problem!



Let's explore this water angle. How so? Will my tank have several gallons of water in it after a time? After 18 months of on and off use I don't think that's the case. As for build up on the pistons and valves, Maybe I should stick a bore camera down a spark plug hole and have a look?

I did some more reading into this. Found a head after a year and a half of E85. Definitely seems corrosion is a valid concern. Also saw some dyno videos on youtube where E85 cooled the intake charge so much the supercharger built condensation on the outside



And here's from a block off a different vehicle. Seems to support the corrosion issue in a DD scenario.


I also found this video, which seems to support the clean burning nature of E85. The engines were ran for 500 hours, but I suspect this was a continuous run and won't show the affect of thermal cycles like shown in the head above

And this neat little comparison where ethanol and gasoline were run, then wear numbers compared

Full paper here: https://www.sciencedirect.com/science/article/pii/S0043164818300450





So, my conclusions are this: Run a few tank fulls every couple years to take advantage of the cleaning abilities of E85. However, due to an increase in wear and corrosion concerns both with the engine internals and metallic parts of the fuel system, I wouldn't find it suitable for daily use where long term vehicle reliability is a concern.

 

[SnowDrifter]

duplicate post please ignore

 

[swathdiver]

I've been out of engine building for a few decades but those center and right side pictures don't look a whole lot different than my Buick blocks after 100K+ miles if memory serves.