towing fuel milage

Turtle n Peeps wrote:

APT wrote:
I'll state it another way. Every gas engine vehicle will use very close to the same amount of fuel when the aerodynamic drag is the same, i.e. sale high walled trailer. So like the OP, I would expect nearly the same mpg from the current V6 as the prior 4-cly assuming the same driving conditions. So my theory is that the driving conditions are not the same, i.e. he is driving faster since he now has significantly more power/gearing/wheel torque available. If he slows down to the same 35-40mp up those hills, then I expect the fuel to fall back in line. If you he is holding 68mph up every hill and freeway overpass, then it will cost more fuel.

Great post APT!

IOW's, A smaller engine at WOT or almost WOT is way more efficient than a big engine at 1/4 throttle making the same horse power.

If people have HP, most of the time they will use it.

Theoretically true, however approaching WOT the ECM/PCM will enrichen the air/fuel ratio somewhat from the ideal 14.7/1.

Best scenario is to maintain TCC engagement through smaller throttle angle if possible as the ECM is trimming most economically and trans temps are greatly reduced.

If a larger engine allows this scenario I am all for it.

My economy has varied anywhere from 5-13mpg depending on the truck/engine, trailer, speed and driving conditions.

Towing just about any substantial trailer with a truck seems to result in somewhere around 10 MPG. To go way above that, seems to require a very small, light trailer; maybe a fiberglass Casita or something like that. I get 7 to 11 towing a 2700 lb. car behind a Class C MH with a v-10 motor. Entirely different set-up but the result is still "around 10 MPG".

68ltd wrote:
I just returned from the first long trip with my new truck and was disappointed in only getting 10 mpg.

The truck in a 2014 Chevy Silverado double cab with the 4.3 v6.
My trailer is only 17ft and has an empty weight of 2300 lbs. I was the only passenger and was loaded very lightly (empty water tank etc.)

For 3 years I pulled it with a 4 cylinder Chevy Colorado and it got 13 to 15 mpg depending on speed. Even though my truck has a v6 it never lacked for power even in the rocky mountains. I started rving with my parents in 1971 so I know towing mpg is never good, but I expected better than this. It didn't change whether I drove 60 or 68.

Any thoughts?

I think 10 mpg sounds about right for a full size V6 truck towing a full height 17 ft trailer. As others have said, wind resistance is a huge factor. The old 4 cyl 5 speed stick Colorado got better mileage when towing and when not towing, so that also makes sense. That 4.3 V6 is a great engine. I remember reading at the time of the new GM pickup introductions 2 yrs ago that the new 4.3 V6 is all new, sharing only the same displacement as the old 4.3 V6 which was based on the old 350 V8. Either way, I think your numbers are about right, except I cannot understand the comment about getting the same mileage at 60 and at 68 mph.

APT wrote:
I'll state it another way. Every gas engine vehicle will use very close to the same amount of fuel when the aerodynamic drag is the same, i.e. sale high walled trailer. So like the OP, I would expect nearly the same mpg from the current V6 as the prior 4-cly assuming the same driving conditions. So my theory is that the driving conditions are not the same, i.e. he is driving faster since he now has significantly more power/gearing/wheel torque available. If he slows down to the same 35-40mp up those hills, then I expect the fuel to fall back in line. If you he is holding 68mph up every hill and freeway overpass, then it will cost more fuel.

Great post APT!

IOW's, A smaller engine at WOT or almost WOT is way more efficient than a big engine at 1/4 throttle making the same horse power.

If people have HP, most of the time they will use it.

APT wrote:
I'll state it another way. Every gas engine vehicle will use very close to the same amount of fuel when the aerodynamic drag is the same, i.e. sale high walled trailer. So like the OP, I would expect nearly the same mpg from the current V6 as the prior 4-cly assuming the same driving conditions. So my theory is that the driving conditions are not the same, i.e. he is driving faster since he now has significantly more power/gearing/wheel torque available. If he slows down to the same 35-40mp up those hills, then I expect the fuel to fall back in line. If you he is holding 68mph up every hill and freeway overpass, then it will cost more fuel.

Agreed. I see your point based on what he was saying about going up the hills a lot slower with the old 4 cylinder. I was thinking just overall.

I'll state it another way. Every gas engine vehicle will use very close to the same amount of fuel when the aerodynamic drag is the same, i.e. same high walled trailer. So like the OP, I would expect nearly the same mpg from the current V6 as the prior 4-cly assuming the same driving conditions. So my theory is that the driving conditions are not the same, i.e. he is driving faster since he now has significantly more power/gearing/wheel torque available. If he slows down to the same 35-40mph up those hills, then I expect the fuel to fall back in line. If he is holding 68mph up every hill and freeway overpass, then it will cost more fuel.

Do a few more trips and your truck will be broken in and you can see if it improves. You never know, you could have a 10 mph headwind that will screw up your mileage on a trip and you wonder why 60-65 mph was getting low mpg. That would act like driving 70-75 mph and that will start killing your mpg's.

I have a Cessna air speed indicator in a center console and pitot tube sticking out of the grill. I can see when I'm "in the draft" behind a semi or coming back from mexico and hitting a 25 mph headwind. No wind with the diesel setup towing in my sig is about 14mpg at 65, with a 25 mph headwind it's like 8mpg, with a draft or tailwind sometimes 18 mpg.

Then there are idiots like, that would luv that 4.3 motor with the 6l90e in an 8600 gvwr 8 lug truck. Gives me the payload I need, decent mpgs, some towing prowess for trailer into the upper 4 digit lb range......

I would still expect around 10-12 towing depending upon the aerodynamics of the setup. low 20s empty at 60-62 on a level with cruise on.

marty

IdaD wrote:

I didn't mean any offense to anybody. I just meant if you trade a 2014 truck to try to improve your towing MPGs, you'll make a dealership someplace very happy.

I assumed that's what you were getting at, in response to a post on page 1 that suggested OP trade his truck in for a more "capable" truck... OP's truck is plenty capable for the camper he's towing. Happy camping!