Falken Wildpeaks AT3W killing mpg?

Hey guys, first post… long time lurker.

Now I know that we all operate on smiles per gallon here. But I’ve been noticing my mileage hasn’t been great. I’m all stock aside from my wildpeaks which are 265/70/17 and method wheels. I have a soft tonneau cover too. Im always hitting around 230-250 miles per tank. Which puts me around 11ish mpg.

I was curious what others were getting so I decided to search and see. Looks like most people get around 15-16 or more with my same set up. I’m in Canada, but our winter hasn’t been bad. Barely any snow, I always keep up on my oil changes and don’t usually drive like a bat out of hell. My truck is a 2008. Bought it used 1.5 years ago. I definitely got slightly better mileage with the stock bald tires on it at the time.

I’m still new to the maintenance of these trucks. Should I look at replacing things like spark plugs to try and get better mileage? Also I know winter blend fuel vs summer blend fuel, you usually get worse mileage but even in the summer time it’s not much better. Maybe 20 more miles or so? And yes I’m using miles because the majority of you guys are American and my truck is from Ohio so it’s in miles anyways lol.

thanks guys.

 

yeah they are the only thing besides the methods. But I’m pretty sure last I checked my methods were lighter than the stock wheels by a little bit. I did get a 27 F battery. Bigger than what was in there but the weight difference is marginal.

when you say tune up, what do you mean?

 

Spark plugs every 48000kms, clean throttle plate and maf during this to regain MPG.

All terrains have higher rolling resistance, simply they will always use more fuel compared to any highway tire.

You increased tire diameter so you're showing 3% less miles than actually traveled. Not a big deal, but add 3% to your calculations.

 

Not just the weight, but aggressive treads are great for traction…but your vehicle has to move those aggressive lugs, that act as resistance.

 

The weight of the wheels and tires matters because it is rotational mass, and increasing that makes it harder to turn. The battery won't factor in any more than if you had some groceries in the back seat. Don't worry about the negligible battery weight gain, but the weight of the tires and the more aggressive tread will make a difference. So will the fact that it's a little taller on those tires. That hurts aerodynamics to a certain degree. Another thing would be the offset of the methods. Do your tires poke out from the fenders more than stock? If so, again, it's taking a bite out of MPGs.

All the little things add up.

 

interesting point about the offset. My offset is 0, so very small poke. I converted the mpg to our litre per 100km and I’ve found some other threads saying 15L/100km is high for the Tacoma, im at 25L/100km which helps put things into perspective for me a bit more. I think something internally could be wrong on top of all those little things.

 

I’ll have to give this a go. I don’t know what those things are yet, but I’m learning. I’m sure YouTube will help

 

I’ve tracked MPGs for every tank over about 4 years now, been running General Grabber ATX tires in the same size as your and they have very similar tread. There is absolutely something else causing your low mileage. I’ve never seen below 14mpg and had as high as 21mpg. Time to do some maintenance.

 

I run methods and at3’s also and noticed a drop in MPG also… they are a heavy combo… I’m getting more MPG then 11 though and I have a shit ton of extra weight

 

There are too many factors that affect a trucks MPG.
Especially a 2008 truck.

From Aerodynamics. (Roof rack, bed accessories ie, cap, tonneau, or other)
Rolling resistance, Cargo weight, typical daily driving weight, tires, engine or transmission condition, etc etc etc.

I understand that you are worried about fuel costs especially here in Canada.

If it is a concern or high priority to you for you and your use case, whatever gear you have onboard on a daily basis leave them at home, reduce any weight that is unnecessary, or aerodynamic drag. Or get a set of street tires for daily driving, then use the AT3 for off-roading.

If it isn’t a concern, just drive. Tacos are not known for fuel efficiency at our class. Especially not our age.

 

Your fuel mileage does sound very low, I have a similar setup of 265/75/16 wildpeaks on FN/konig wheels, 16x8 0 offset so little bit of poke, otherwise mostly all stock besides a mid rise bed cap (~175-200lbs) and a 1" spacer lift. I'm still getting around 18-20, lowest ever was like 17. Before my wildpeaks and bed cap I was around 19-21mpg with my tonneau.

Something seems off in my opinion, might be how you're calculating mpg, tire pressures, something with engine operation, brakes dragging, etc.

 

With those tires, I typically get 19-21 mpg, 17-18 mpg with city driving(traffic) or lots of slow off road driving.

 

You said you only had slightly better mileage with the tires that were on it. What were you getting then?

Are you sure there are no other mods to the truck?


Oh, and I just noticed you said 230-250 miles per tank. What was your math on that? I drive til my light is on, and then some, before I fill up. I seldom hit 18 gallons when filling up. Even your 230 would be 12.8mpg, 250 would be 13.9mpg. So yeah, tell us how many liters you are putting in your truck after how many kilometers. Maybe your math was a little off?

 

Any noticeable difference in mpg between the two stock factory sizes? 245/75 to 265/70 16?

 

I was going to say the same thing. What does OP consider "per tank"? 16 gallons? 18? etc. Like you, rarely ever need to add more than 17 gallons and I average about the same mileage and I think I'm in that 13.5-16 range.

Looking at a couple recent ones....
(Not corrected for tire size, so add a couple tenths to the average mpg)

16.09 gallons @ 224 miles = 13.9
17.19 gallons @ 261 miles = 15.2

So by my calculations, he's getting somewhere in the 14mpg range. Acceptable, if you ask me.

 

You changed wheels too? Which tire did you LT or P? Methods are heavy ass wheels.

 

With Falken Rubitrek LT235/85/R16, steel Toyota oem spare wheel rims.
I’m getting about 15 mpg on mostly shorter (guessing median of 15 miles) mixed city/highway trips, winter driving, back often filled with moderate amount of stuff maybe 600 lbs average including driver + cargo + passengers and hard tonneau cover.
Some sizes are only available in LT tires, not in P tires.

I think i was getting slightly better mileage before winter with P265/65/R17 on the oem aluminum wheels.

Using tire pressures at or close to either door or the tiresize converter pressure calculator, for door P vs LT, which puts LT psi recommendation at ~43 i think.

I was expecting to still get at least 18 mpg on average, and before i got the truck, i expected 20+ would be routine. But, gasoline is still relatively cheap compared to other expenses.
Easy way to improve mpg is only drive downhill with the wind at your back.

 

I get consistent 17-18 mpg with my 235/85/16 AT3W tires, but I went with pizza cutters for this exact reason. Running stock TRD OR wheels on my SR5 as well. One other thing is that might help my MPGs is I drive it like a truck, I dont mash the pedal at every light and I drive very conservatively.I'm never early or late, I arrive precisely when I intend to.

 

Miles per tank is useless information. Fill it up, set trip meter to zero, drive it until you're below 1/4 tank then fill up again. Divide miles driven by gallons you used. That is miles per gallon and useful information. Even at that you'll really need to do it for at least 2 or 3 tankful's and get an average to know anything.

If you never did this before buying the tires you have no baseline to know how much, if any worse you're doing.

I doubt if your tires are the problem. My 2007 has 244,000 miles on it. I'm on my 6th set of tires if I include what came from the factory. I've had 265/70/16's, 245/75/16's, and 265/75/16's on it. I've had 38 lb P rated tires, and 53 lb E rated tires. My fuel mileage has never changed. It gets 16-17 for my normal everyday driving and 19-20 mpg on the road.