Real life MPG numbers wanted.


I posted a question on the RV.Net site about 6 months ago asking truck camper folks how to increase fuel milage. I wanted to know if anyone had increased their mileage with fuel additives or computer chips etc.... Just about everyone said don't waist your money, just drive 60 mph and that will give you the best results! So on the trip I am currently on, I have been driving 60 mph and I must say, mileage has been good, about 13 (12 -14 range) the entire time! I am loaded heavy too! The best thing about driving 60 is that I can stay in the right lane and the rest of the traffic passes me. It really is a lot more peaceful driving when not trying to pass truckers when I drive 70 or faster. I also see a lot more things from the right lane driving 60 mph. So driving 60 mph gets my vote for the best way to improve mileage, see more and have a lower stress trip! When I need the extra power to pass someone or merge to the left, my big diesel named "Bertha" has the power. I wouldn't go back to a smaller gas truck no mater the size or weight of my truck campers in the future!


Not exactly what you're asking for, but FWIW:

2000 GMC Sierra 2500 (3/4 ton), 6.0L gas V8, 4L80E (4-spd) automatic transmission, 4WD, extended cab, longbed, stock suspension, 245/75/16 wheels/tires (stock size), no heavy add-ons (i.e. stock bumpers, no winch), with Northstar TC800 pop-up camper (8-foot length, fits entirely within bed, but tailgate must come off). Most of the time when traveling, there is a large 4-bike rack on the rear hitch, with 2 to 4 bikes on it -- not sure how much this matters in terms of MPG on this truck though.

Real world MPG at 65mph max: 12 hwy, hand-calculated. I've seen 12.5 (slower highways, 55mph), and occasionally 11.5 (higher speeds, say 70-75), but almost all of the time it's right around 12 mpg. Truck has plenty of power, but I try to go easy on the accelerator to keep the MPG as good as possible.


Hey Kevin

What kind of mileage are you getting with your Tundra and pop up? That's the route I'm planning on going. Wanna take my kid to the National Parks and camping all over the place.


Thanks guys, keep em coming.
Any more gassers out there?

Dieselandmud, what are you doing to get that mileage, thats what I'm shooting for!
@ Oni - I get 13ish with the camper on. I'm going to sell it, if your interested PM me.

High Water

Baja Bliss
Why is my MPG so bad in comparison

2009 Dodge 3500 DRW Cummins, 6 spd AT - no modifications
2006 Lance 1130
14' x 102" cargo trailer filled with bikes
Total scaled weight loaded for a 4 day weekend 18,000 lbs
I live in western CO so no mater which way I go its mountains

are you ready... 8.5 mpg Calculated at the pump consistantly, computer in the truck is optimistic.

Yea it sucks! I've been thinking about putting a pop-up on my first generation Tundra and getting a small trailer.


8.5, ouch! But that is alot of weight (and fun!) you are hauling.
I'm selling my Tundra and FWC if your interested...


I have a 2002 7.3 auto F-350, DRW Crew Cab (the black one and read family) 4x4 4:10's, running loaded not givin a care as to mileage (or any mods yet) 10-11. My old 2000 F-550 (the one with the black fender flares/tarp) 7.3 manual 2WD 3:91's SuperChip (on lowest setting), loaded for bear (17-20K) 11-14 (highest ever 16. weighed 12,500 empty). Replacement for the 550 is a 2000 F-550 V10 auto 4x4 4:88's crane truck (Hiab knuckle and log bed), gets 11 mpg empty with foot your of it, on flats, any load or hills 6-7mpg. and Good trucks. The gasser is a local truck, the 350 is my over the road"er" . Good trucks, can haul about ANYTHING you care to put on them, ESP. F-450/550's. They are SERIOUS trucks. I am converting my F-350 to a 450 via, springs, mounts, rims/tires (19.5's). Likely I will find a 4x4 F-450/550 to swap axles over to get bigger brakes as well. The heavier the better up to the 550 (F-450 and 350 share the Dana 80 rear, just dfferent brakes and hub). Front axles/springs are the same 350-550, hubs and brakes change.

Something worth noting, ( I currently own both deisel AND gasser) the difference between high test gasoline and Diesel has begun to grow, and as that continues the math on the diesel "advantage" becomes less important, and this is especially important as you mull over a "bigger truck". If you can find a medium (F250 ish) truck that can work for you, the bigger diesel makes less mathamatical sense also, depending on how much tripping you do vs. around town. I especially like hopping in the V10 in the dead of winter to plow snow. So, I guess add in the "how far north are you and how colds does it get" factor.


camera 1! 363.jpgOF-550.jpgphone 240.jpg Jronwood
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I have 2000 f350 crew cab dually, 4x4 auto with 3.73 gears and usually travel 70-75mph. It has a super chips tuner, exhaust, down pipe, and an intake. It will be getting a trans soon so hope fully all these numbers go up some. It scales by its self 8600lbs. My camper is a 10.5' older real lite (or not so real lite). Empty weight on the campers is about 2300lbs, loaded a little over 3k. I have a 14,000 lb gvwr equipment trailer and I usually haul my 87 k5 rock crawler on it. The empty weight of the trailer is 3500lbs, the k5 6200lbs, 500lbs tool box and usually 500lbs-750lbs of coolers, tools, spare parts, firewood for 5 days. On the highway the best is see empty is about 19 mpg. When I put my 10k trailer behind it (no camper) about 15 mpg. When I have my camper by it self my gross weight is usually 11,600 lbs and my best mileage is 11 mpg. When I combine my truck, camper, trailer, and k5 together my gvwr is over 22,000lbs and I will still see 11 mpg. My range for fuel (stock fuel tank) with truck empty is around 650 miles. The best I have ever gotten with just the trailer and the k5 on it was 535 miles. The best with the camper on the back was about 400 miles. We also live at the foot of the mountains and all our recreation time is spent in the mountains. Vail pass, Monarch pass, Eisenhower tunnel, Floyed hill, Wolf Creek pass, and La Vita pass are all very common to pull at those weights. If we went east at an easy 65 I think some of those numbers might be a little better.


New member
1994 crew cab long box with a 460 and OD auto 4x4. 9.5'camper and a 7000 lb trailer, gross weight is 17,400 lbs. I get 8.6 mpg at 60-65 mph.



I have a 98 TJ with a 2.5 ltr, soft top,it's got g2 Dana 44's, 5.13 gears and 33x 12.50's. I get 16 or so and 14 loaded for a trip.

I live in the hills above Denver so it's always uphill. I want to see what it's like in the flats.


I currently have a 2006 Corsair 9'2" that has been on 2 different trucks. The first truck was a 2004 Chev 2500HD 4x4, ext. cab, long box with the 6L gasser and auto trans (with minor mods - Banks exhaust, cold air kit, controller, air bags, 265/75-16 AT tires, etc.)
During a 9000km trip to Alaska, the Yukon, and Northern B.C. a few years ago, it averaged about 9.5 mpg fully loaded. There was alot of highway (not much of which was flat) but also a fair amount of gravel (Top of the World Highway, The Dempster, Telegraph Creek, & Granduc Mine). The rig would get as much as 11 mpg on a lazy flat terrain highway trip.
The second and current truck is a 2007 Chev 2500HD 4x4, crew cab, long box with a Duramax and 6spd Allison. It has a 4" Rancho lift (with RS9000 shocks), 305/75-16 BFG AT 10 ply tires, air bags, but is otherwise pretty much stock. This truck handles the camper even better - loads of power/torque (365hp/660 ft lbs) and the suspension is fully adjustable to control the higher up weight of the fully loaded Corsair. I generally get about 11 - 14 mpg depending on the highway, conditions, and speed. When we are going out for a weekend of playing in the wilderness, I tow a 16' enclosed toy trailer, but have never bothered to keep track of the mileage. The pic below shows the '07 nose high as I had extra (unforeseen) weight at the front of the trailer, it typically sits level.
I plan to stick with diesel and will be getting a higher weight capacity truck next time around.


Thanks guys, keep the info coming.
Motrhed, great to see a direct comparison between a gasser and a diesel. Where I am (NW MT) those mileages pencil out to a $43 savings with the diesel over 1000mls. Would take a while to overcome the extra price of a diesel at that rate. How have the maintenance costs of the 2 different trucks compared so far?


2006 Ram 3500 QC 4x4 Srw
5.9 Cummins 4spd auto 3.73 factory tire size.
Lance 825 -2500 lbs loaded with gear/water

12-13 MPG avg at 70mph, Best 15 MPG on flat highway. 18-21 empty consistanly, all numbers hand calculated. Truck was stock with the exception of a Intake.

I recently added a smarty programmer and will be playing with it this spring/summer to see if it will improve.

I had basically the same truck with a hemi and the same set up netted me 6-7 MPG:Wow1:. It was a pain to drive in the mountains it spent most of its time in second gear.

The maintenance difference for me is tiny, A hemi holds 7L of oil a cummins 10L price difference is minimal, the fuel filter is reasonable and cummins brand oil filters are dirt cheap. Other than that a diesel can be more expensive to fix bits and pieces wise, but will have 2-3x the life span of the best gas engines out there if looked after.

Diesel fuel is the same price of gas here.

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