What MGP are you getting on your 8.1 empty and allso towing?
I just sold my 6.0 i was getting 14 mpg empty and 9 mpg pulling a 4000lbs trailer.
Looking at getting a 8.1 and pulling a 5000lb trailer just wanting to see what the fuel milage difference will be. From what I read it sounds like it will only be 1 or 2 MPG.
Thanks

got 16 once with my reg cab zf6 with 4.10 gears 4x4 got about 7-8 pulling my 40ft enclosed that ways 22k

11 empty interstate 78mph. Got 14 a few times, but RARE!!!!!! Usually 9, thats all conditions from in town stop and go to little freeway to interstate. Have seen 5 before :( but oh well. I average about 9. Towing in the hills, i got 7-8, interstate towing, well ive seen 11 but its a mix from 8-11 usually. All depends on hills, its MOUNTAIN country here

I usually get 11-12.5 on the highway, probably 9ish in the city; empty, full, or towing an aircraft carrier.
I have a crew cab, 4.10 gears, leveling kit, 1" block in back, 33" mud tires, and a lead foot.
Haven't towed too much, but one time I did, was about 6k, and I got 12.2 in a 200 mile trip.

There are real mountains here. :D

I got about the same with my 08 6.0L, equipped almost the same (gears, lift, tires, foot, etc). Freeway was a tad better in it though.

8 to 9 mpg for the past 3 years. thats a 07 work truck

13 on the highway at 65 empty

9 towing 13k 38 foot offshore boat

I will also throw out there,,,, this is after adding the fiberglass tonneau cover

I usually get 11-12.5 on the highway, probably 9ish in the city; empty, full, or towing an aircraft carrier.
I have a crew cab, 4.10 gears, leveling kit, 1" block in back, 33" mud tires, and a lead foot.
Haven't towed too much, but one time I did, was about 6k, and I got 12.2 in a 200 mile trip.

There are real mountains here. :D

I got about the same with my 08 6.0L, equipped almost the same (gears, lift, tires, foot, etc). Freeway was a tad better in it though.

Thanks for the input. I figured it would get close to what my 6.0 got. How does it pull. I am also from Utah and yes we do have real mountains, that is why I needed something more than the 6.0 to pull with.

Thanks for the input. I figured it would get close to what my 6.0 got. How does it pull. I am also from Utah and yes we do have real mountains, that is why I needed something more than the 6.0 to pull with.
Well Ive got a tune, injectors, and a little custom work, but no BIG power adder. And mine tows awesome. Some of the grades around here are forbidden for road tractors to set a tire on them!! And Ive towed 9-12k on them. It IS going to hunt for gears but not like a 6.0. Mine stayed in 3rd and 4th the whole time, usually 3rd around those SOB curves. My fathers 6.0 will drop to 2nd on the interstate doing 70....its sad. But it has been ragged also. So IDK how a 'good' 6.0 feels.

My old 02 8.1L used to get around 9-11 mpg regardless of the type of driving, towing, etc. Never over 11.5 but never under 8 either. Hope that helps some. Definitely notice some improvement in power and response with an exhaust and intake upgrade on that truck. Most improvement of any gas vehicle I have ever owned that I put an intake and exhaust on. If I can help with anything, let me know.

Easy to figure at fill ups 20 gallons and you went 200 miles.
Put over 100k on an 01 8.1 10 mpg almost always.

I get 10.5mpg hauling my 2500lbs work trailer. Mostly because of lack of aerodynamics... I normally see around 11.5 to 12 with one trip at 14 going to flagstaff and back.

My o6 gets 6.5-7 @ 11k lbs , 4.10 rear (just the truck) My dads is the same and he gets 8-8.5

check out my thread i did on my gas mileage its very detailed, i have another one to do when im get my self to put it all togeather. Ready all 2 pages i messed up my first calculation the official one is one page 2 Average 9.11MPG doing every type of driving there is.

http://www.dieselplace.com/forum/showthread.php?t=375232

My Avalanche has an 8.1 and I get 13 loaded or unloaded. I pull a 24' enclosed trailer when I do pull with it. I have 4.10 gears and 265-75-16 tires on it.

Im getting 9 MPG city, 14 hwy, 7-8 pulling 9k w/ my avalanche

My mileage is pretty much all highway and at 65 mph (highway speed limit). There are hills around here also. I've been getting 14-15 unloaded and 9-11 pulling the 21' 5th wheel.
I also have the ZF6. My mileage dropped a bit going from 245's to 265's. My only tank of gas at 16 mpg was with the 245's.

I usually get around 7-9ish. I have 35's on it and I am loaded with a winch and many tools and other crap in the back. Not bad for a lead foot and 348k on it.

I get 10... No matter what. I've towed 36' 5th wheels to open car trailers. I get 10mpg...

Ordered brand new in 2000. Sunset Orange Metallic, crew cab, 4.10's, Allison, every option but skid plates. 71,000 miles, original spark plugs, wires, etc still.



Amsoil in the motor, trans, transfer case, and rear.

I have gotten 14 hwy on new oil empty, and I have gotten 6 on new oil pullin 13k..I just made my trip from Springfield Mo to New Bern NC pulling about 5500 lbs on a trailer and 800lbs in the bed and the worst tank I got was 8 in the mtns, best was 11 on the reletively flat ground in the eastern part of NC.

I couldnt be happier with my truck, cruzing up Black Mtn at 70 mph towing my jeep.

Mike

cc, 4:10's. Get around 8-10, but that is mostly in town. Never goes above 12... ever. Wondering if one of the mail order tunes could so something about that!

I usually get around 7-9ish. I have 35's on it and I am loaded with a winch and many tools and other crap in the back. Not bad for a lead foot and 348k on it.


Dude, 348k? That is friggin' rare.