I just completed a week of mileage testing on my truck.
I have a 46 mile commute each day and 37 miles of that is in a 65 MPH zone. It takes 3 miles to get to the highway from my house and the drive is rural at MPH.

After the 37 mile 65 MPH zone I get into a 4 mile stretch of 50 MPH then off the exit into city stop and go for another mile or so.

I drove 5 days and only had a single 1 mile trip added. I kept my speed at 55MPH maximum and achieved 22.2MPG. The overhead computer indicated 18.8MPG.
I filled at the same pump and filled to the exact same level. I have checked my speedometer with my GPS unti and it is dead on.

I am repeating this experiment at 70MPH in the 65MPH zones to see the difference.

My torque converter is fried and really has no lock-up left in it.

 

Zip, zero, nada! Oh, you meant without a load

 

Well maybe 200-300 lbs in the bed.

 

calculated mileage....winter 14 at best mostly city short trips with a 250 mile trip on every other weekend. -20 F low temp. minimum idle time.

summer...22.5 absolute best, normal 20.0 mostly city with 250 weekends. 45F min 90 F hi.

All highway at 65 or less generally 60. 65 costs about 1 mpg except with tail wind. I watch the weather and flags for otimum speed.

I keep rpm under 2000 except in 5th. Few races and smoke outs.

I run 65 psi in the front 55 rear no load. with load 65 rear. Michelin's. Caution these tires are not worth a flip in the winter or when it is wet . ..even worse than that. They are great highway tires and last forever. I have almost 100k miles on them and there is still another 15k left.

A week or so ago it was really nice and I did a bunch of rat racing and just good old feeling my oats.....17 mpg OMG. If you row it through the gears you can almost see the gage go down. Sure is fun to let your hair down once in a while. Net cost difference was $7.70 at the pump for the weeks oil. I'll just forego the donuts at coffee time at work for the week. I'll lose a few pounds in the process that wouldn't hurt a bit. Maybe mpg will pick of .1. haha

bentwings

 

Mileage..

mostly empty truck bed and a couple hundred in toolbox i get approx 16-18 in the city, and 19-22 on the highway with a best of 23 mpg.... at 70 mph at 2000 rpms on 285 liberators, oh and thats with tailgate up.. Note my pickemup truck is a 12V...

Tx

 

Never have an completely empty bed. There's always something back there...pallets of crete, a barrel of oil or twenty bales of alfalfa. On the farm, runnin' the back roads or the irrigation ditches, 20 mph top speed.....about 30mpg. On the local two lane road running 45 mph top....about 22 mpg. Out on state highway (not interstate, cuz that's a hundred miles away) 65 mph.....about 15-16.

 

2000 2500 4X4 6 speed. 21 - 22 cruising at 70. 18 - 19 in town. 13.25 towing my enclosed at max speed of 65 mph. ~11 towing my 5'er. Since I'm paying for the fuel, and I'm cheap, I blow very little smoke and drive fairly conservative.

- JyRO

 

when I bought, in the end of Jan. and drove home Ms. to Mn. driving hwy 65 thats through small towns , so mixed driving I got 19.5 , then mixed driving in Mn. with winter fuel 17.5 now I'm getting 19.5 , temp. avg. 60f.