Pentastar 11hr road trip E85 or 87?

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I'm about to embark on an 11hr trip from Chicago to my home state of MD. I just purchased a 2013 Chrysler T&C Van from FB market for $2500 230k miles formerly a fleet vehicle. The oil was changed out to PP HM 5w30. Should I run E85 since it's prolonged constant rpm and speed or 87? It's 2.99 but I only get 14 gallons of combustion out of the 20 gallons I put in. I'm looking at it from a cost perspective, but also an effective means to give the 3.6 a good deep cleaning from the prolonged combustion.
 
With the E85 prices, you end up consuming more than you save. Only real upside is the increase in power if your vehicle was specifically tuned for the benefits. The constant speed with such a long highway drive will be fine IMO.
 
What about the cleansing properties of E85? I've read that it's very effective at cleaning carbon from 87 or other petroleum dominant fuel. The only other downside I've read about is the OCI will be more often since more fuel is needed to combustion, which results in more contaminants in the oil.
 
Would E15 be a better optionin the long run? There's also 88 gas that I've seen at some stations
 
Do the math...for your specific vehicle. Some make better use of E85 than the difference in BTU might suggest due to the cooling effect of ethanol and the knock resistance that allows more aggressive timing.

I ran it almost exclusively in my Silverado with a 6.2L that required premium. More power, more performance, and just a small hit in economy...and cheaper overall.
 
E85 is better at cleaning out the fueling system, but won't do too much to clean the pre-existing carbon off pistons. There are usually less heavy fractions in E85 than conventional pump gas, which may help prevent generating new, undesireable carbonaceous deposits. Even if cleaned, E85 often will still leave behind a carbon film.
 
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I know years ago when I did the math, I had to have a 70 cent spread between E85 and RUG to break even on my flex fuel Ranger.
However, it runs like a scalded ape on it, and anecdotally speaking runs smoother on it, and after a tank of it as well.
I'll run a tank through it when the margins are right to clean it out; however, generally the spread is not there to run it on a regular basis especially with a 3-4 MPG penalty for doing so.
I'd do RUG for most of your trip, with an occasional tank of E85 if the price differentials align favorably.
 
For cruising down the highway, I believe Atikovi's take is the simplest and best answer. If the cost saving offsets the loss in fuel economy it's fine. As a very frequent road-tripper, I've seen E85 up to 30% cheaper, which makes it a no-brainer in most cases. On the other hand, one of my local stations sells E85 for 10 cents less than regular unleaded per gallon. No thanks.

These discusssions often presuppose every E85 outlet is actually serving up E85. When I still had my 2014 T&C, most (not all) pumps I used had a disclaimer label stating something to the effect of the fuel consists of ethanol content between 51% and 85%. As someone who tracks every tankful, it seems the alcohol content indeed varies.

For instance, I'm pretty much a speed limit/cruise control/right lane kind of guy. With a tankful of regular unleaded and a standard load (me, wife, and some luggage) I'll typically cover 430-440 miles before having to refill with 17-18 gallons, which puts me in that 24-25 mpg range. This is my rough benchmark.

There's a Meijer station I frequent in Milwaukee for its cheap E85 before heading back south. On this fuel we pretty consistently eke out 380-390 miles, good for 21-22 mpg...up to a 16% loss. I've used this station dozens of times over the past 6-7 years, and the results are pretty much the same, so it's kind of my E85 benchmark.

Another station I hit rather frequently is a Casey's in rural Arkansas, whose E85 is often 25% less than their unleaded. Surprisingly, every time I used their E85 the van exceeded 400 miles of range, once hitting 425 headed south. I'm pretty sure their ethanol content is less than 85%.

What does this all mean? I don't know...just rambling on my E85 experiences. In my case, as a careful, economy-minded driver, E85 has been a satisfactory fuel choice if 1) you're highway cruising, and 2) the cost is at least 20% lower than regular unleaded.
 
It's worth a shot just to try it out.

When I had my 2014 Grand Cherokee, I got terrible mpg on it, 20%+ less. But it seemed to run really good.
 
I find alternating fillips at half a tank yields the exact same mileage as running E10. E10 to half a tank then top off with E85, take to half a tank and top off with E10.

Here in Central IA you can find E85 priced almost a dollar less than E10, so even a full fill up pays to run. E15 is 20 to 30 cents cheaper as well.

I like to use E85 to cleanse the fuel system, as someone asked above.
 
Does anyone have a UOA from using E85 exclusively? I'm so questioning the degradation effects on oil from E85 and weather a prolonged road trip would offset the degradation due to the heat boiling off excess moisture from e85
 
you’ll get better mileage on the 87 and overall the engine would run better with the octane. It would probably be a wash cheaper fill ups but will just be putting it out the tailpipe.
 
I would run it on E85 the whole way, regardless of "savings". Cleaning benefits are worth it to me. Then simply change the oil, along with other fluids. But that's just me.
The single long run on E85 is not enough to kill the oil, but I simply would change it along with other fluids as part of preventative maintenance on a cheap new-to-me vehicle. I'm gonna guess that maintenance history is unknown at that price tag? How's the transmission?
 
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