Gas Mileage with payload (Help I'm dumb)

Okay, so I'm trying to figure this gas mileage thing out.

I use my Tacoma for my side job, stock suspension wheels and tires. There's usually 180 pound me inside, as well as around 100~ pounds of tools and equipment.

About 50% of my driving is done with between 300-1000 pounds of crap in the bed. Mixed city and highway driving. My average load is 300 pounds.

My gas mileage average is 11 city, 13-14 highway. (200-something medium miles per tank.)

Since the 4.0 V6 only makes 236HP, can my gas mileage drop be solely associated with the engine working harder to carry the combined weight of all of the crap? Again, 50% city and 50% highway. With no load, I get very similar numbers.

Is it as simple as that? I just replaced the plugs and got my tires at the correct PSI but it's not making much difference. Theoretically, I would assume if I got a truck with let's say 375HP and a V8 I would get better gas mileage.

 

Yep before lift tires etc. hauling my fuel mileage dropped like that but I also carried a bit more weight my truck also weighs a little more than yours before too. I was about 13 mpg city and 16 hwy with around a 2-3000 lb payload towing avg though. Now with lift and tires it's like 8-12 mpg mixed. These trucks loose a lot of mpgs hauling anything.

 

Yes it is probably the 300-1000 pound of crap is probably what your issue is. I usually don't put anything in my truck and average about 15-16 mpg. These things aren't good on gas. I believe the winter mix gas also cuts your mpg down a bit.

 

Appreciate it! The weight may be slightly over, I've got to inventory all of my tools and equipment and get them into the formula as well.

 

Ah, gotcha. Thanks!

Right about now, I'm thanking myself for not lifting/putting big tires on it lol. Might be in the single digits then.

 

Yeah, you'll be surprised at how much weight adds up pretty quickly.

Single digits suck. Last haul I did was 6 canoes on a trailer, gear, and some other stuff. Probably close to 3000 lbs or so and my trip I got 9. I also used down hills to my advantage to gain speed and then just kept even throttle up the hill and scrubbed all my speed. Instead of trying to keep a steady speed up and down hills. Driving style can help a lot in fuel mileage. In the city you're just screwed though.

 

You'll not see much difference in fuel mileage. My Tacoma has done 3 road trips from Georgia to either the Grand Canyon or Colorado. All 3 times it carried 3 adults and was loaded heavy with camping and or hunting gear. The payload on my truck is only 1200 lbs and I have a 180 lb cap on it. I weigh 220 so that only leaves 800 lbs for other passnegers and gear. I was pretty close to that on every trip. Fuel mileage on 2 of those trips was right at 20 mpg, the same that I get unloaded.

One hunting trip involved a 28 hour sprint both ways only stopping for fuel, food or to swap drivers. We drove as fast as we thought we could get away without being stopped and my fuel mileage on that trip was closer to 18.

FWIW I hunted Colorado in November and made a similar trip with my 2014 F-150 4X4 supercrew with the 5.0 engine. I was carrying similar weight with hunting and camping gear. I got just shy of 19 mpg going out. Coming back it was 17.9, or about 1 mpg worse. About 1 mpg worse than my Tacoma.

I've had the Tacoma for almost 12 years, the Ford 2 1/2. There isn't enough difference in fuel mileage to worry about and the Ford is much more powerful and comfortable. But the Tacoma is a smaller more compact truck with advantages of its own. I'd much rather drive it off road and with it approaching 200,000 miles I've spent next to nothing on repairs. Time will tell about the Ford.

Lifting trucks screws up the aerodynamics and more aggressive mud tires have much more rolling resistance. Each one of those modifications will cost you 1-2 mpg. Combined it could mean as much as 4 mpg. Both of my trucks have stock suspensions. I did upgrade to slightly taller E rated tires with an all terrain tread. My fuel mileage on both trucks is exactly the same as before.

 

That's some pretty awful figures. I'm going to guess you're really goosing it? When I'm maxxed the fuck out hauling my camper, or am towing at or near GVWR I don't see numbers that low.

Edit: 10 ply tires on my ride as well

 

20? With close to full payload? I can only dream of 17, without full payload. Stock everything.

 

I drive pretty slow. Under 2k pretty much 60% of the time. I guess it's city traffic.

 

I got 21 hwy 65 mph cruising light unloaded. Full payload just the truck loaded no trailer I was around 18-19. Now if I cruised at the posted speed limit or 5-8 over there went the mileage.

 

Wonder how I get such shit gas mileage to be honest, haha. Most of my highway driving is done in the mountains though. That may explain it.

 

Yeah if you are up at elevation and are mountain driving mileage goes down. I know the mountain driving I've done my mileage suffered down to 17-18 hwy.

 

Virginia, so the elevation isn't terribly high. Still do most of it at around 70-80 MPH though.

 

Something to keep in mind from a physics standpoint, extra weight generally only hurts your mileage when you do lots of stopping and starting. If two trucks, one empty and one with 1000 lbs, accelerated to 60 mph once and drove that like until they ran out of gas on flat land they'd go almost the same distance. But if they continually went 0 to 60 to 0 to 60 etc the empty one would go much further than the full one.

Also I disagree that a 375 HP V8 would get significantly better mileage than your engine working harder. It takes a certain amount of energy (gasoline) to accelerate a certain mass to a certain speed. There might be minor differences in engine efficiency but energy is energy, doesn't matter how many cylinders it flowed through.

 

I’ve always noticed a big drop in mpg when driving 60 to 65, 70, 75 and so on, even when I had stock tires. I get great gas mileage when it rains and traffic is only going 60! Then I see the biggest drop at 75 and above.

 

Tacomas suck for fuel economy

 

Yes, they do for being a smaller truck.

However, we didn't buy a truck for best mileage so we have a solid truck that rarely breaks down for any of us and that is gold.

My 4-door 4WD automatic V-6, on California ethanol-diluted gas gets 15 mpg mixed driving and 16-17 mostly highway.

If I do long trips and have no load and keep it at the speed limit (65-70 in California and 65-75 in Arizona) I have gotten 20 mpg.

In Mexico, where the gasoline is pure, my mileage goes up and with heavy camping loads, I get 18+ mpg. The worst 2WD mileage is when City driving only, in the summer, 14 mpg.
4WD gets way less, and since I also deflate when off road, can't get accurate mileage figures, but it would seem to be closer to 10-12 mpg in four-wheel-drive, off-highway driving.

 

I've never carried heavy loads far enough to really test how putting 1,000-1,500lbs in the bed impacts gad mileage.

Having a couple hundred pounds in the bed shouldn't really be that big of a deal. That's a couple 6 foot male passengers.

Willing to bet your mileage is probably more of your driving habits.

I have a DCLB TRD Sport on stock suspension but upgraded 265/70/17 tires (1.4'' in diameter larger). I get 17mpg city and 19 mpg highway in the winter. Add 1-2 mpgs for the summer without the winter blend fuel.

Don't rev your engine over 2,000 rpm. Especially not when hauling anything heavy. Let torque carry you not HP. It's not a sports car.
Brake early and coast down to speed when you can to avoid using your brakes. Leave reasonable car lengths between you and the person in front of you do you don't have to slam on your brakes.
Also don't drive over 60-65mph. As soon as you go faster mileage will tank. Your MPGs definitely look like they reflect driving habits over what you are carrying payload wise.

 

That's worse than a first gen! Getting ~17mpg mixed city/highway with my '97 fully loaded in the cab and bed with tools/construction materials.

You could try cleaning the MAF sensor? Cleaned mine when I bought my truck and noticed a significant improvement in gas mileage... it was caked in probably 20 years of grime, so it couldn't have been working at optimum efficiency. I was probably getting around 12-13 mpg when I first got it, with an empty load, highway driving only.