2010 4 cyl 4x4 AC taco, 16mpg and sluggish uphill. whats wrong?

I have a 2014 Tacoma, Access Cab, 4X4, 4cyl, 5 speed manual, with 1200 miles on it. I added a topper and I got rid of the crappy Dunlop tires, for Michelin; 265X70X16. Initially, and before the changes, I was getting between 19-21 MPG. Now, it is absolutely ridiculous; between 13-16. Granted, it is a very, very cold winter in MN, and I warm up my truck every morning for about 10 minutes, and all my driving so far is city driving. But still, if I had known it would be this bad, I would have gotten a bigger/more powerful engine. Not too happy with this. Love the truck otherwise though.

 

i get better MPGs with my V6 than i did the 4 banger, with all the hills around here i think it was just working harder all the time, i hated it, sluggish as hell

 

The bigger more powerful engine would burn more fuel, if used the same way.

Last couple of weeks, when there was either six inches of snow on the roads or temps went to zero, I was getting 16s and 17s.

Last tankful, temps were in the low teens snowless glare ice roads (smooth rolling), I almost got 21. I have a good bit of data to be found in my fuelly sig. The really low summer dips are when I tow my 5-ish thousand pound trailer.

Also, unless I'm sitting in the truck doing paperwork, I never idle. When you idle, you're getting 0mpg...

 

My '09 4wd, 4 banger access cab with 5-spd, camper shell, and a couple hundred pounds of extra crap gets a consistent 25+ mpg in the Arizona mountains at the altitudes you mention. The tires are 245, load range E, at about 35# pressure. It slows down on the steep hills, too. My guess is that a lot of the difference between your truck and mine is the tire sizes and driving habits. No offense intended. I had a lead foot when I was younger and my gas mileage showed it. Afterthought: My gas mileage with this truck improved after the first 2 or 3 months I owned it. I bought it used with about 28k miles. Yours might improve with time, too.

 

Good proof that it can easily be done. It's amazing also how good mpg you have when you pair the right gears with the right size tire. Stock 245s with stock 4.10s I was getting 22-24. Went up to 285s with 4.10s and got 20-21. Put a lot of armor on, went up to 315s with 4.88s (the right "stock" gear ratio) and I get 19 now. I averaged 17 on my last offroad adventure. I drove 400 miles to a park, spent 3 days offroad mostly in 4hi and 4lo, then drove 400 miles back home. Ultragauge said 17 somethin.

It also really helps to calibrate your speedo when you change tire size. Your mileage will always be off it you don't. So if you are running 285s instead of 245s with stock 4.10s then your speedo will read less miles then you have actually traveled and will consequently make your mpg calculations off

 

D'oh!

Summabish, I completely overlooked this!

*nuclear powered, weapons-grade facepalm

 

Thanks for the feedback regarding resetting the speedo, and running 265's with factory 4:10's. That is probably the biggest factor. Believe me, I run the gears right all the time; around 2300 rpm, and I don't drive crazy (I am not a youngster, I am an old fart). Will just have to see what happens when weather warms up. Appreciate all the feedback.

 

What the..... I must have a rogue ghost truck or something. I got the 4 banger 5 speed in an '09 regular cab and it is one peppy truck. Granted it is lighter than the AC but it lives between 7,000 and 9,000 ft. And, the best part is I always get between 23 and 25 mpg. I don't get why some Tacos seem to get horrible mileage and others sip fuel. That barometric sensor on the intake has had me wondering for a while whether it could substantially affect mileage on different but similar trucks.

 

Mines an 08 reg cab L4 5 speed and I'm in the same boat. I can't believe some times that there are Tacos with this engine and transmission that AREN'T peppy.

I don't confuse it with a 400-horse V8 like I used to race. But for what it is, and the mileage I get, I've never one time thought to myself "Gosh, I wish I had some more power"

Hell, I've wished for more cab noise reduction in Florida rainstorms a lot more than I've wished for anything else. Put a gun to my head and I'd say better brakes under load and maybe stock 16 tires would be complaints 2 and 3. But I bought it *because* it's a fleet work truck with no frills and no power windows, so I knew what I wanted going in.

 

I did't calibrate my speedo when I went to 235/85, but I check the odo from time to time against the Garmin on the dash on a 100km trip. I add the 3.9% when I do my Fuelly entry (my fuelly sig shows more mileage than my odometer.)

 

Yeah the calibration is def a big deal. Unlike the v6 model, our speed sensors are located at the wheels so the sensor is reading tire revolutions. Obviously a bigger tire takes a greater distance to rotote 360 degrees meaning that your distance traveled will be greater then a smaller tire. Your speed sensor knows no difference other then point A to point B equals one revolution.

As said a few times also that driving habbits are key for mpg. For me, it's cool having a ultragauge because it reads real time and average mpgs. I find myself watching them all the time and almost challenging myself to keep the average up high. It's surprising sometimes to see how doin certain things gets my better mpgs then others. For instance, I notice that shifting under 2k gets worse mpg because the motor has to work harder to speed up. Seems like there's a lot more torque in the 2.5k area and keeping the rpms in that range makes it effortless to hold a speed and makes my foot very light on the pedal. Goin down a straight road at 40mph I watch the instant mpg gauge sit between 35-40. I never floor my truck, hardly ever idle it and drive according to how that gauge reads giving me the best mpg. And yes, if I floor it at even 1500 rpms in 5th gear that gauge instantly goes down to 10 mpg. It's not hard to get really bad gas mileage but it's also easy to get really good gas mileage.

 

Duh, idk how i over looked this. thanks for helping with that now i need to find how to re-calibrate to the bigger tire size.

thanks

 

I don't have to recalibrate my speedo, from going from 245X75X16 tires to 265X75X16 tires, since that is only a change in the width, not diameter.

 

your diameter should change as well.

245 x .75 = 183.75mm
265 x .75 = 198.75mm

so the diameter of your wheele would have changed by 15mm x 2 = 30mm = 3cm

thats over an inch in diameter change.

 

Ive found the problem?

 

Yeah tires are really strange. They never match when it comes to width and height changes. Ive always been confused by that. Haha

 

LMAO , this should be the reply to the 20 threads per day we see on this topic