Multiple catalytic converter failures in multiple vehicles

[Gary Gere]

Isn’t non-ethanol relatively uncommon? I rarely see it available, perhaps try “normal” top tier fuel and see if it makes any difference? You’re not putting in any additives correct?

In Montana (and Canada) almost every gas station's 91/93/94 octane fuel is "ethanol free". Exxon has both ethanol free and 10% (?) ethanol 91 premium. I believe this is because all small engines (such as tractors, snow blowers, chain saws, etc.) require non-ethanol fuel. I always use "ethanol free" fuel. I talked with Kalispell Ford's tech and mentioned what you said. Their reply was they dont think its the fuel because "everyone uses it". They are now looking for an oil "leak" into the engine / exhaust system. If it was one engine I might agree but three 3.5L eco-boost V6s in a 12 month period?

I can get 10% ethanol 91 fuel from Exxon - do you think that would be better than the ethanol-free fuel? It is a lot cheaper ($3.32 vs $3.96)

Are you adding anything like octane booster or heat to the fuel?

I have never used any additive of any kind - the only thing that goes into the fuel tank comes out of the gas stations pump.

 

[Old-Raptor-guy]

In Montana (and Canada) almost every gas station's 91/93/94 octane fuel is "ethanol free". Exxon has both ethanol free and 10% (?) ethanol 91 premium. I believe this is because all small engines (such as tractors, snow blowers, chain saws, etc.) require non-ethanol fuel. I always use "ethanol free" fuel. I talked with Kalispell Ford's tech and mentioned what you said. Their reply was they dont think its the fuel because "everyone uses it". They are now looking for an oil "leak" into the engine / exhaust system. If it was one engine I might agree but three 3.5L eco-boost V6s in a 12 month period?

I can get 10% ethanol 91 fuel from Exxon - do you think that would be better than the ethanol-free fuel? It is a lot cheaper ($3.32 vs $3.96)

I have never used any additive of any kind - the only thing that goes into the fuel tank comes out of the gas stations pump.

How in the heck are they making non-ethanol fuel in the 91+ octane rating??

I am no fuel chemist so if someone knows please speak up.

With the removal of LEAD and then MTB it is my understanding that without ethanol it is pretty hard to get above 88.

Ethanol is an a octane booster and your truck was designed to use it, do not be afraid of it.

 

[New recaros]

How in the heck are they making non-ethanol fuel in the 91+ octane rating??

I am no fuel chemist so if someone knows please speak up.

With the removal of LEAD and then MTB it is my understanding that without ethanol it is pretty hard to get above 88.

Ethanol is an an octane booster and your truck was designed to use it, do not be afraid of it.

Isooctane and isobutane are both 100 octane and commonly used in boosting octane. Ethanol is 108-109 octane but lower in energy or btu per unit volume than gasoline.
If you can get non-ethanol fuel of higher octane you should make more power and use less.

 

[Old-Raptor-guy]

Isooctane and isobutane are both 100 octane and commonly used in boosting octane. Ethanol is 108-109 octane but lower in energy or btu per unit volume than gasoline.
If you can get non-ethanol fuel of higher octane you should make more power and use less.

Forgive me if I am wrong, but 100% isobutane IS 100, to get 94 octane from regular gasoline which is 87 octane, would require a 50/50 mix.
Butane stiochiometric air/fuel ratio is 8 to 1, vs ethanol being 9 to 1. So 50/50 gasoline/butane would give 94 octane and have about the same MPG as E85 which is 102-105 octane.
If butane was the answer we would see it more common.
8-1 air fuel ratio vs 14.7 - 1 of gasoline, you are not running that out of a pump without tuning.

 

[Gary Gere]

These are images from various stations - "ethanol free" / "no ethanol" fuel (not sure about the 110) in Montana.

 

[New recaros]

Forgive me if I am wrong, but 100% isobutane IS 100, to get 94 octane from regular gasoline which is 87 octane, would require a 50/50 mix.
Butane stiochiometric air/fuel ratio is 8 to 1, vs ethanol being 9 to 1. So 50/50 gasoline/butane would give 94 octane and have about the same MPG as E85 which is 102-105 octane.
If butane was the answer we would see it more common.
8-1 air fuel ratio vs 14.7 - 1 of gasoline, you are not running that out of a pump without tuning.

It’s a feed stock, how the refiners frac it I don’t know. I was in natural gas processing and one of our products we called gasoline was loaded with iso butane and they, the refiners, wanted it. The vapor pressure was 5 times what car gasoline is so they had to remove the butane with an iso splitter.

 

[New recaros]

I looked it up and yes, there are many mixtures to get the required vapor pressure and octane.
These two compounds outline the two extremes of the scale, with pure iso-octane having a rating of 100 and n-heptane having a rating of zero. Thus, a blend of 90% iso-octane and 10% n-heptane would have an octane rating of 90.[2]

 

[thatJeepguy]

I looked it up and yes, there are many mixtures to get the required vapor pressure and octane.
These two compounds outline the two extremes of the scale, with pure iso-octane having a rating of 100 and n-heptane having a rating of zero. Thus, a blend of 90% iso-octane and 10% n-heptane would have an octane rating of 90.[2]

Fascinating, what was using this fuel?

 

[MORaptor1]

I live between Whitefish and Eureka - moved here in 2012 - unfortunately after "covid" people started moving here from California and they want to change Montana - it’s frustrating and disappointing.

I know. I’m from Colorado. Lived there until 05’. The mtn west is gettting all the locust from CA and their liberal garbage….that they moved away from. I’d still like to return.

 

[Raptured22]

We are getting lower quality fuel. I use ethanol free 93 and I have noticed a lot more condensation coming from tail pipes. When you leak water from your tail pipes constantly, you have shit fuel!