Took a little trip from St. Louis out to Little Sahara OK this weekend and was rather shocked at the low MPG that I got. Total weight truck, trailer, 4 four wheeler, gear,and four guys topped out at 15,040 lbs. Total round trip mileage was 1300 and we burned 132 gallons of fuel for a rather low average of 9.8 miles per gallon. Now I will admit that I ran around 75 to 80 mph where I could so the RPM’s were definitely up there, but I never would have guessed I would get that low of mileage with that little weight.

Truck ran good, pulled great, only lost minimal speed on a couple hills but man I think that is terrible fuel mileage??

Your guys thoughts??

 

You were going too fast - period. Wind resistance is also a factor - not sure how you were set up. More rpms=more fuel burned. You want to keep rpms up out of the 'lugging range' but even empty, once you get up over 70, your mileage drops at an alarming rate. I towed the same amount of weight as you did recently from OH to FL, through the VA mountains, and got 14.8 doing 65-70. Doing 55 i get 16-17 with that setup. Not sure any faster than 70 because I don't go that fast with trailers.

 

As fast as you were going that sounds about right. Pulling my 6 to 7K pull behind high profile toy hauler through the CA mountains (numerous long 7 and 8% grades and 14% or steeper grades on the 2 lane switch backs) I get around 12 mpg. When I get on the freeway grades and do 70 mph I drop down to 10 mpg real quick. With my 3.73 48RE overdrive in the hills it lugs too much at 55 mph so I usually do between 60 and 65 mph on the mountainous freeway and get between 12 and 14 mpg.

 

I was going a little fast, but traffic was minimal and the truck just pulls so darn good when you keep her wound tight, I was just figuring I would get around 12 or 13 mpg and was shocked when it came in around 10 or so. Thought maybe something was wrong?? Plus I really didnt think 8000lbs was that much weight for this thing, guess I was wrong

Plus all my buddies kept heckling me that there Big BLock Chevy could do the same speed and get 10 mpg and I spent the extra just to get a diesel???

 

just pulled a 12k load from boise to denver and back...(that counts the goosenecks weight)...and i drove hard....pretty much 65-85 mph..the whole time...my average was 8.5 - 11 miles per gallon for the 1,600 mile + trip...
not happy...but what can you expect..? a gasser pickup couldn't even pull that load...

 

I know too many people with big block Chevy in rollbacks. They have dreams of getting 10.

 

I'm gonna call BS on 10 mpg with a big block Chevy....well, maybe they do get 10 EMPTY!! For me, I'll never own another gasser, I'm hooked.

 

Dont get me wrong I love the Cummins great power, easy upgrades, reliability (hopefully) just thought it would get a little better mpg.

I saved my big block for my 72 chevy 2wd.... although I dont worry about mpg when doing holeshots at stoplights and big burnouts

Pquestad - were you pulling with the Ramifier on, does that help you mpg's???

 

Similar load, maybe even slightly less weight, I've seen 6.6 mpg IMPERIAL with a 460 Ford.

That's like 5.59 mpg, HAND CALCULATED!!!!!!!! No B.S

 

doing 80 mph without traffic is death on mpg I know running empty at that speed mine is about 16 mpg, add a bunch of traffic and 20 mpg is pretty easy. they need help in the draft much more than the 2nd generation front end.

 

You can increase your fuel economy 60 percent by reducing your speed 30 percent. Once you get these motors over 2200 RPM the start using fuel.

Casey

 

See how your buddy's BBC is doing after 100k miles of this type of work...

 

Guessing you're pulling a cargo trailer. Speed is a fuel killer. For me pulling the car hauler weighing around 7k lbs I'm getting about 11-12mpg running 65-70mph.
So 10mpg would be about right if your running 80.

MikeyB

 

Actually I doubt any small block will do any better than 10mpg pulling a load like that at that speed. I've never had one that would.....

 

I'm going to Little Sahara 1 week from today, I'm going to be loaded to about GVW on the truck, 3 bikes in the box, and 4 guys. Pulling a small enclosed trailer with 5 bikes and all our gear and camping stuff in it. I'll let you know if my results are much different, I'll be setting the cruise on 75 once I hit the Missouri line. Do you have the 4.10's or the 3.73s in yours?