87 octane vs 89 octane, fuel economy differences

[Enve46]

Crazy how the gas trucks get the same or worse then diesel

Yup, by 1.5 mpg for me. But the worry over diesel fuel, filters, cost etc certainly isn’t worth it.

 

[Rockcrawlindude]

Crazy how the gas trucks get the same or worse then diesel

What rock have you been living under? Gas trucks have always gotten less mpg than diesel.

 

[JustARam22]

Yup, by 1.5 mpg for me. But the worry over diesel fuel, filters, cost etc certainly isn’t worth it

It sucks to maintain for sure, but in pulling power you cant compare.

 

[gimmie11s]

Crazy how the gas trucks get the same or worse then diesel

Hasn't it always been that way?

What's crazy, or sad more appropriately, is how the diesels in 2024 fail to get better than 15 or 16 mpg combined. They (the diesels) are going the wrong way.

 

[JustARam22]

Thats due to tighter and tighter emissions requirements, and how to push more power/torque numbers.

As we keep seeing with all the diesel scandals.

V8s really haven't gotten all that much better. Most are going to v6 turbo or 4 cylinder turbo to keep up with stricter emissions

 

[Crusty old shellback]

What about the elephant in the room no one has addressed.

Who buys a 2500/3500 truck for the gas mileage?

 

[gimmie11s]

Thats due to tighter and tighter emissions requirements, and how to push more power/torque numbers.

As we keep seeing with all the diesel scandals.

V8s really haven't gotten all that much better. Most are going to v6 turbo or 4 cylinder turbo to keep up with stricter emissions

It wasn't that long ago that the BEST gas offerings gave around 250-300hp, had massive displacement, and returned 9-10mpg on a good day. Think GM vortec 7.4/8.1 or Ford/Mopar v10.

Today the gas motors are making 450hp and MPG is actually UP 20-30% vs what I mention above.

Yes, diesel motors also continue to get more powerful, however their efficiency continues to worsen -- not the case with gas motors.

 

[JustARam22]

What about the elephant in the room no one has addressed.

Who buys a 2500/3500 truck for the gas mileage?

Agreed, but this entire discussion is about fuel efficiency

 

[Firebird]

What about the elephant in the room no one has addressed.

Who buys a 2500/3500 truck for the gas mileage?

I agree, I definitely didn't buy the truck for economy purposes! Just found the economy vs octane difference somewhat interesting

 

[Firebird]

It wasn't that long ago that the BEST gas offerings gave around 250-300hp, had massive displacement, and returned 9-10mpg on a good day. Think GM vortec 7.4/8.1 or Ford/Mopar v10.

Today the gas motors are making 450hp and MPG is actually UP 20-30% vs what I mention above.

Yes, diesel motors also continue to get more powerful, however their efficiency continues to worsen -- not the case with gas motors.

Remember the days of towing in a GM dually with a 454? You were lucky if you got 5mpg!

 

[dieselscout80]

What about the elephant in the room no one has addressed.

Who buys a 2500/3500 truck for the gas mileage?

That’s why my commuter is a hybrid Lexus ES300H.

 

[Grey]

Remember the days of towing in a GM dually with a 454? You were lucky if you got 5mpg!

Hell I remember when I had a 77 Lincon Mark, 460 engine. I don't think it did much over 5. Low fuel light, was on every other day. Yes it was new at the time, Yes Im old now..

 

[AH64ID]

No hemi experience, but on engines that would actually compensate for octane the mpg improvements have never been enough to counter the added cost per mile of the more expensive fuel. I’d use higher octane when towing, but for around town it never was cheaper despite the mileage increase.

Crazy how the gas trucks get the same or worse then diesel

Why is it crazy? Diesel has more BTU’s per gallon.

 

[Crusty old shellback]

That’s why I commuter is a hybrid Lexus ES300H.

I use my Power Wagon as my daily.
Sold my '73 K5 Blazer with 450 HP 475 TQ and 10 MPG and my '01 F250 V10 with 10 MPG and bought my '21 75th AE PW with 13 MPG.

But now I'm retired so don't have to drive the 5 miles to work each day.
Just the 30 miles to town when we decided to leave the mountain.

 

[Firebird]

Hell I remember when I had a 77 Lincon Mark, 460 engine. I don't think it did much over 5. Low fuel light, was on every other day. Yes it was new at the time, Yes Im old now..

I had a 1975 Mark with a 460, man could that thing drink some gas!

 

[Enve46]

It sucks to maintain for sure, but in pulling power you cant compare.

Pulling power is a nonissue to me as I never used the truck for its intended purposes which is again why its not worth it to me.

The 6.4 has plenty of power and when not driving around town it gets very near similar mileage as my diesels Ive had, minus my 2013 G56 truck which was in the mid 20s. Ill get 16/17 highway with 37s on the PW and I was getting 17.7 mpg with my mega cab on 37s. For my uses, the diesel was costing me more and more of a headache. That DOESNT mean the diesel is worse and thats not my argument. People who use diesels for their purposes, Id own one as well. But being back in a 6.4 Hemi truck with the 8 speed, has plenty for all I do and the occasional trailer it will have behind it.

 

[gimmie11s]

Remember the days of towing in a GM dually with a 454? You were lucky if you got 5mpg!

I had a 1999 vortec 454 suburban, 4.10 gears... great truck, loved it. A reprogrammed ECU made it a hell of a runner. But yeah, towing our 8500lb bumper pull toy box netted about 6-7mpg if I was just cruising 65 mph lol

10 unloaded

 

[gimmie11s]

Ill get 16/17 highway with 37s on the PW and I was getting 17.7 mpg with my mega cab on 37s.

 

[flan]

Downhill, with a tail wind.

 

[gimmie11s]

Downhill, with a tail wind.

at 45 mph