MPGs with 3rd Gen Tacomas (4WD)

I bumped up tire size to 265-75-16, and I may have around 100 lbs of "aftermarket" stuff, none of which would affect aerodynamics much: Pro Skid, Greenlane Offroad Sliders, OEM Tonneau.

MPG hasn't changed much over life of the rig. 18.8 MPG combined average over 40k miles according to Fuelly.

What I DO know is that even a light headwind on the highway kills MPG, like really bad. I think aerodynamics makes or breaks efficiency on this truck.

 

2021

2wd, 3"+ lift, 285/75/17(33.8"), no added weight.

Manually calculated 14.2mpg. thats all city. I've done highway only(@80mph) and get @17mpg.

 

Stock 2016 Sport, MT. 90% 2 lane roads (I live 150 miles from any Interstate). 20.5 avg before adding a GFC camper (255lbs) now 19.2 avg. A 110 mile trip into the neighboring state and back will hit over 21 for the trip, no steep hills or mountain passes there. I was a life long backpacker, so my camping setup is less than 100lbs including water and none of it is carried except when camping.

 

2” lift, 33x10 tires, front stump bumper, winch, sliders, bed racks roof rack and RTT. So about 650# of extra weight.

Im still able to get stock MPGs if I drive conservative.

Premium SFOB tune on 94 E0

That’s 21 MPGs right there.

 

2020 Taco w 265/75/16 E rated KO2's stock suspension
18.6 mpg avg daily driving, mpg dropped from 19.1 when I went with the e rated larger tire.
2900# Sunray camper dry weight, loaded I'm not sure of weight. In the hills of east tn in 5th w ect on, 14.2 mpg avg on last trip 500 miles
1425 #21 ft Bass Tracker boat 17 ish local

 

If you care about fuel efficiency, you can probably go about it differently. Lifting the truck an inch or two and changing tires to a larger diameter probably won’t change where you can go off-road. People do this stuff for aesthetics more than performance. That’s totally fine but you can’t turn around and whine about MPGs when you should have seen it coming.

 

The story you saw is entirely possible, but it also depends how they drove vs how they normally drive. Rotational mass makes a big difference. One analogy I saw said every lb you add to your tire weight is equivalent to 20 lbs of payload in terms of how hard your truck has to work.

As for my personal experience: I put stock size tires on that were less than 5 lbs heavier than stock (I don't remember the exact weight) and saw probably a 1-2 MPG drop on my commute.

I also drive with the setup you see in my profile photo from time to time. I don't have exact weight figures, but I'd say it's probably maxed out or slightly more. I'll get around 15-18 MPG with that setup depending on the speeds I'm doing. However, without the bikes and some of the weight (tent still attached), I can probably get around 1 or 2 MPG worse than my mileage without it.

Aero matters more than weight, but weight still matters. One Rivian reviewer maxed out his payload and kept the object below the level of the cab and saw very little drop in range.

 

Wow, quite a response. Thanks for the slam about my education which, by the way, set my up for many successful years as an engineer. What a wonderful "welcome" to this fairly new member. Of course the laws of physics don't change. Of course I know that. But in that "laws of physics" are a million tiny details - a Subaru engine optimized for performance at a certain fuel flow that sucks if you push it any further. A Ford diesel that had so much torque and power that it almost didn't give a crap what you put behind it. A Ford V-8 that was pretty tolerant of extra weight and load. While this next statement is not something I've researched specifically, my observation for most gas engines in any type of vehicle is that when you start adding load to them (on the vehicle or a trailer) that there seems be a point where MPG falls off a cliff. The engines are designed for good performance when your within some expected power load. But when you go into "that zone" it's a lot like flooring it out of an intersection. The engine basically says "Screw it - he wants to go! Throw all you've got at it Scotty and damn the MPGs".

 

A really massive thank you to everyone that added their personal MPG stories here. That is EXACTLY what I was looking for, and I sincerely appreciate you all taking the time to comment here. That all seems more in line to what I was expecting vs. the 11 mpg guy I mentioned in the beginning. By choice I drive easy with a light foot and that keeps me on the better side of MPGs. I am sure I'll refer to this thread over and over as I start to build out my rig with a somewhat reasonable expectation of how this will affect things.

 

If you are planning on doing an MPG-conscious build, check out my build thread if you’re curious. I think I have found a pretty good balance. Current pic of my truck below, I just drove it across the country and back and I would say I averaged around 18-19mpg on the highway. Link to my build thread:

https://www.tacomaworld.com/threads/clean-purpose-built-3rd-gen-sr5.734054/

It’s normally over 20mpg on the highway but I had a ton of gear in the back and we did a lot of mountain passes which killed MPGs. When I do trips to the Outer Banks, I average 21-22mpg for the entire trip because that is much more flat driving.

 

My humble opinions:
Weight will almost always be bad for mileage....but not if it is a straight back camper shell, IME. On longer highway trips to the interior of the province, my mileage is exactly the same with a high top camper shell. I think the the air flow off the back of the camper shell is cleaner than without the cap. 250lbs and no mileage difference on the highway. In town it decreases my mileage.
Light weight tires/rims will make a HUGE difference as it is rotating mass. I lost 18lbs per wheel (72lbs total unsprung mass) going to 215/85 R16's and saw a 12% increase in mileage, less noise, and WAY better acceleration. I LOVE skinny tires for multiple reasons (wet weather/ snow traction, MPG, etc.)
Keep it below 60 mph makes the biggest difference.
There is some debate as to accelerating; there is some evidence that accelerating quickly saves gas, as you have much less vacuum to overcome from a small throttle opening found with gentle acceleration (Research it. Seems counterintuitive at first, but after researching it, makes sense.)
AC on the 4 cylinder is known as the AnChor, or "engine brake" as the compresser really adds drag, probably not an issue in your case.
I regularily get 25 mpg in the summer.
Winter, man, these trucks hate winter!

 

32” tires (255/75/17), 4.88 gears, Blackhawk tuned for gears truck weighs 5,400lbs full tank of gas 17-21mpg, 10-12 towing 4K lbs.

 

That is great real-world feedback. Thanks!!

 

I get 16.8 avg mixed city/hwy MPG as shown by the computer. That’s 17.6 adjusted for oversized tires.

For how much weight I carry and how modded out I am, that’s pretty good. But I made compromises to achieve that. Also my specific choices were made to preserve highway range.

I highlighted in red what I’d return closer to stock if I wanted better MPGs.

• 275/70r17 Nokian Outpost AT (E-rated) (47 lbs)
• Koenig Six Shooter wheels (22 lbs)
• CBI aluminum front skid (~20 lbs)
• Greenlane Stump aluminum front bumper (45 lbs)
• Smittybilt 9500 winch w/ synthetic line (~50 lbs)
• Greenlane aluminum sliders (50 lbs)
• Outgear HC rear bumper (~100 lbs)
• Extreme LED light bar
• Diamondback SE tonneau with aluminum extrusions bolted to it (~85 lbs)
• 2” lift, OME/All pro progressive AALs
• Blue Sumo springs
• Rago hangars
• 4.88 gears
• KDMax tune

 

Look ’em up

 

You’re welcome! Let me know if you have any questions. All the sizes and stats of my build and stuff are in the build thread if any of that helps.

 

@GDCoop welcome to the forum

Not build related but something I felt was an interesting observation on the cost of drag:

I recently took a trip pulling my utility trailer. It is the standard 5 x 12 landscape style with a 4 foot high mesh tailgate/ramp vertical at the back and weighs 990 pounds empty.

Normally without the trailer on a steady highway run at 65-70 I will see 21-19 mpg, higher speeds really hit the mileage on these trucks. Downshifting is very seldom require on hills at highway speeds.

Running with the empty trailer was 15 mpg at 65 with much more frequent shifting required for the hills. It was windy that day and I could feel it hitting that gate.

I have pulled the same trailer with an elderly F-150 (302 V8), it got about 12 mpg all the time with or without the trailer.

 

As everyone already pointed out, weight is the big killer of MPG. I went from 19-20MPG bone stock to 15-16MPG after adding a Decked system (fully loaded), and the Uptop Overland Alpha Roof Rack and Bed Rack system (equal height to haul 4 x 8 sheet goods) on stock 16" tires. I'm at the limit of the stock suspension when hauling lumber, and my next mod will be new suspension but that's not going to help MPG.

 

What app are you using to track MPG and fill ups? I'm tired of using the Notes app on my phone.

 

Op, Welcome to TW BTW. This is an excellent forum and my only social media. It's still the internet, and people are people. Don't let the nay-sayers and rude folks get to you. The "ignore" feature is useful for the persistent thorns ... and our Moderators do a solid job enforcing the CoC and dropping the banhammer on those that don't get it.

I wish you well as you research and determine your build/mods for YOUR truck. Remember it's your truck, you are the only one who you need to make happy.