I know a few of you guys have 8.1 trucks on here. What is the mileage that I can expect if I DD it? I've got a 25 mile commute one way, and I was just wondering if it would kill me or not.
CK5
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8.1 Mileage
- Thread starter swettysblazer
- Start date
I'm trying to figure out if the 8.1 or 6.0 should be the way to go in a tow rig.
Biggest engine wins every towing contest!..MPG wont be much better with a smaller engine,might even be worse!...often a larger engine gives more MPG because it isn't working as hard and you wont have it floored all the time..
Ummm, I thought you bought a first gen powerstroke to use as a tow rig? So why are you asking about a big block tow rig then?
Though a 8.1 would be killer in the K5
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Though a 8.1 would be killer in the K5
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So my 5.9 cummins should get destroyed by all these 8.1 gassers then?
Lets get real here, daily driving a 496 (even a modern one at that) is going to kill you fast with today's gas prices. We have a 2500hd with the 6.0 at work we've put 150k miles on and it gets about 13-14 unloaded. Period.
Expect less from an 8.1
63chevyll
1/2 ton status
My 8.1 around town was about 8-11 mpg. I remember always coming up with 10.
My MI dropped when I did exhaust and K&N. And bumped tire to a 285 70
Highway 12-13 constantly. Only once did I get 14+
I would defiantly own another.For a BBC I've never had a 454 get above 8. So ill take the 8-11 any day with the gobbs of TQ they have.
My MI dropped when I did exhaust and K&N. And bumped tire to a 285 70
Highway 12-13 constantly. Only once did I get 14+
I would defiantly own another.For a BBC I've never had a 454 get above 8. So ill take the 8-11 any day with the gobbs of TQ they have.
Most people report getting 12 - 13 mpg with their 8.1L engines. Pretty much the same as a 6.0L
Ummm, I thought you bought a first gen powerstroke to use as a tow rig? So why are you asking about a big block tow rig then?
Though a 8.1 would be killer in the K5
Long story with that, that I don't want to get into right now. Long story short, I'm selling it.
There's a lot of 6.0 trucks around here. My friend has one and he loves it. Just gotta go back to the drawing board I guess
So my 5.9 cummins should get destroyed by all these 8.1 gassers then?
Lets get real here, daily driving a 496 (even a modern one at that) is going to kill you fast with today's gas prices. We have a 2500hd with the 6.0 at work we've put 150k miles on and it gets about 13-14 unloaded. Period.
Expect less from an 8.1
OK,I should have said biggest GAS engine...comparing it to a diesel is not what the original question was...of course the diesel will have better towing ability and deliver better fuel economy...especially a cummins,a 6.2 or 6.5 would not likely do much better than a gas engine and be slow and gutless,unless they had a turbo..
In my experience with older carbed engines,big blocks did slightly better as far as fuel mileage than a small block beating itself to death trying to pull heavy loads or weight...my 454's fuel mileage only went up or down maybe one to three miles per gallon whether the truck was empty,fully loaded,towing or plowing...at best I could get 13-15 mpg empty and usually got more like 10-12 ,no matter what I was doing with the truck..
I know what you meant, I was just poking fun at ya.
Oh and to add to the question at hand the 6.0 chevy gassers are great trucks. They are a good option for a dd/tow rig and they're priced right for what you get.
If you like poor fuel economy, and lots of shifting.
Martin
Martin
79rustyk10
3/4 ton status
Id look for an 8.1 over the 6.0. Even for just a dd. in my mind the added torque more than makes up for the 1-2 mpg the 6.0 might get better.
Then I'd have it tuned.
Then I'd have it tuned.
63chevyll
1/2 ton status
Im going to add a different perspective. Ill start with the 6.0
The 6.0 is a great engine and I like it a lot. But the 2500s that have the 6.0
Will have a 14 bolt FF or the 9.5 and a 4L80 (4speed)
The 8.1 will be in a true 2500HD a more stout of a frame, a 11.5 AAM rear end, an Allison trans (5 speed) big radiator and all coolers. the 2500HD is pretty much the same truck as the dmax without the diesel.
I know how many people swear by the 6.0, but factor in where you live. Here in Colorado we are high elevation and have lots of hills...where the air becomes thinner.
If your a low elevation flat land tow person then a 6.0 will be great.. but if you need the extra balls the 8.1 is where its at for a gas truck. Also...consider what you will be towing.
So. If I'm pulling a heavy load and my foot is pegged all the time and the engine is struggling then I dont give an F what my mileage is if I can't even safely pull a load while tearing the truck up
The 6.0 is a great engine and I like it a lot. But the 2500s that have the 6.0
Will have a 14 bolt FF or the 9.5 and a 4L80 (4speed)
The 8.1 will be in a true 2500HD a more stout of a frame, a 11.5 AAM rear end, an Allison trans (5 speed) big radiator and all coolers. the 2500HD is pretty much the same truck as the dmax without the diesel.
I know how many people swear by the 6.0, but factor in where you live. Here in Colorado we are high elevation and have lots of hills...where the air becomes thinner.
If your a low elevation flat land tow person then a 6.0 will be great.. but if you need the extra balls the 8.1 is where its at for a gas truck. Also...consider what you will be towing.
So. If I'm pulling a heavy load and my foot is pegged all the time and the engine is struggling then I dont give an F what my mileage is if I can't even safely pull a load while tearing the truck up
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I picked up a dirt cheap 2005 HD a few years ago to fix and flip. It had a 6.0L and 4L80 with 4:10 gears. After driving it for 10,000 miles I don’t see where a 6.0L holds anything over and 8.1L. Both the 2001 with the 8.1L and the 2005 with the got practically got identical fuel mileage but if you put a car trailer behind the 6.0L it would turn into a snail and actually consume more fuel than the 8.1L pulling the same load. The only advantage of the 6.0L truck was it was much quicker and athletic to drive around town but I attribute that more to the auto trans over the dump truck shifting ZF 6 speed in the 8.1L truck.
The only time I checked the fuel economy in my ’78 with the 8.1L was a on a 1,500 mile trip to Southern Utah and Western CO. The trip was a combination of highway and off-roading. The average MPG for the entire trip was 11.72 MPG. I don’t think that is too bad for an 8,000 lb rig with 4:56 gear and the aerodynamics of a drive in movie theater screen.
The only time I checked the fuel economy in my ’78 with the 8.1L was a on a 1,500 mile trip to Southern Utah and Western CO. The trip was a combination of highway and off-roading. The average MPG for the entire trip was 11.72 MPG. I don’t think that is too bad for an 8,000 lb rig with 4:56 gear and the aerodynamics of a drive in movie theater screen.
Larry, I was hoping you would chime in. There's an 8.1 truck for sale near me locally and I was thinking about going to check it out. I am planning on towing my Blazer with it. The off road park I frequent is two hours away, and I am planning on going back to Michigan again this year and I really don't want to drive the K5 if I don't have to. I would also be using this truck as I said as a DD. I don't see many of them around. The farm I worked on last year had two of them, and they were complete workhorses. 6.0s are a dime dozen around here, the big block is a rare bird however.
Just curious
What did you ever end up going with?
What did you ever end up going with?
Nothing yet, on the hunt though. I can't keep driving my K5 out to the wheeling spots, sooner or later it's gonna bite me in the ass.
True dat! I don't wanna have to drop your tcase every time you come out 
Speaking of which, I really need to re-seal that again
