4 cyl. gas mileage

Yeah mine probably needs some work to get the MPG back up lol.

 

I am also running aFe CAI, I have been using it last 75k. I though about installing some headers.

 

I had a K&N drop in filter but I started having some dust go through it. Caught it within 60 miles of driving and went to the auto store and called K&N. Their response was my truck was at fault and their air filter was up to spec. There is no performance gain by running an aftermarket air intake system or filter other than noise.


Rant off now.

My issue is probably a few weak cylinders, little oil consumption and maybe a small coolant leak.

 

Mine is a 2004 4X4 with the 2.7. I average very close to 20 mpg. I've gotten as high as 23+ and as low as 15 when I do a couple of days of off roading. I try to cruise on the interstate at 65 or 70 mph on my 15 mile drive each way to work but since I live in a 75 mph state I run at 75 or 80 when the traffic is heavy during "rush hour" because the Ford SuperDuty's will run you over at times. So will anyone else when they are in a hurry.
I idle my truck a lot. I very rarely just start it up and go. 99% of the time it is at, or very close to operating temp before I put it into gear especially in the winter. I never turn it off when I stop for a short time at a convenience store. Because it gets so cold where I live there are many times I just lock it up and let it idle when I go shopping for 30 minutes or so in the winter time. Many others do the same where I live.
I average 20mpg winter running 87 octane and summer running 91 octane and I live at close to 7000 feet. I've run premium for the most part since I bought the truck at 119,000 miles. Premium isn't needed but it is more highly refined and has less "crap" in it. I figure the engine runs cleaner with it and I can't put my finger on it but the truck just seems to run better with the 91 octane. The difference in fuel mileage between 91 and 87 is almost imperceptible as far as I can tell although the 91 seems to be a slight bit better.

 

22.5 avg. for 3 years straight. magnaflow exhaust, afe dry filter. 245/75 stock wheels. Everything else stock. Mostly highway driving.

 

2010 ac manual 4x4 2.7, 80k, 265/75/16 duratracs.
Just bought the truck two months ago. First couple tanks, 19 mpg. Not happy. Changed the muffler out to a flowmaster 50 and keeping the RPMs below 2500, been getting 22 mpg now.

 

MPG dropped slightly after getting wider/heavier tires and adding a bed toolbox. Average over the last year and a half is listed below in my signature.

 

2015 4x4 Access cab automatic, 265/70/17 BFG KO2s, 15k miles, averaging 17-19 mpg. Mine seems to be fairly low compared to others, but the wheel/tire combo probably has something do to with that. Also I have a pretty heavy foot and I do 50/50 city/freeway driving.

 

I'm running 265/70/17 BFG KO2s. I've been annoyed with my 16 mpg average even on highway trips. Lately I stopped using cruise and I noticed i was able to keep it around 21.5 mpg. This is with the larger tires and the front air dam removed on my 2016 aces cab AT.

 

The KO2 BFG rubber has quite a bit of rolling resistance compared to many other AT tires. I'm running Toyo Open Country AT II 245/75R16 on my 5 Lug and get close to 20 if it's only highway and steady at 70-75 anything over and it's more like 17. The 2.7 is too underpowered to efficiently move that big heavy rubber. Oh well, the truck still runs and gas is cheap so I'm happy. I used to be in the oil field and so I would rather burn more gas and diesel so the surplus goes down lol.

 

The truck is a 2003 2RZ 2.4l with the extended cab and a 5 speed manual transmission.

I have a high profile Snug Top shell.

My tires are 205/75 15 on the stock 5 lug wheels. I roll with 35 psi tire pressure and Chevron 91 premo.

At 65 mph in 5th, the

$152 ScanGauge - SG2 II Ultra Compact 3-in-1 Automotive Computer with Customizable Real-Time Fuel Economy Digital Gauges , Black , 5"

scan gauge reads 2500 rpm.

The speedometer reads high; 65 mph indicated is 63 on the scan gauge, and the scan gauge matches all of the radar speed warning signs we have around here so I think it is accurate.

The odometer is very close though, it reads 30.7 miles for my commute which Google maps puts at 31 miles.

The commute is mostly highway.

The last tank of gas was 374.1 miles with 14.376 gallons or 26.02 mpg. My best tank average was 26.5 mpg with a long string of excellent traffic patterns during my daily commute.

Can I really expect to do much better?

To get that mileage, I keep the speed below 65, use the cruise control as much as I can, coast to stop lights and through exit ramps when possible, and slowly accelerate. The commute time is such that I can avoid most traffic snarls - stop and go kills MPG!!

The truck needs new tires soon, and I am not sure if I should stick with the 205 or go up to 215 75 15 or 225 75 15. I think the wider tires might have more rolling/wind resistance.

I don't notice a big difference in fuel economy in 4th or 5th gear between 50 and 65 mph so maybe air resistance is the major factor in that speed range.

Has anybody compared the 205, 215, or 225 tire size fuel economy?



EJPHI

 

19-22mpg depending on configuration 09 4x4 4cyl 5spd armour, tool box, 315/75r16 bfg ko2 e, 4.88s pro comp steel wheels

 

28.4 is the best I've seen. Confirmed with a calibrated Scangauge 2 e. Highway speeds of 62 average with downhill assisting me (a little cheating so maybe 1.5 less)

245/75/16 stock tires with secondary air filter delete- AFE dry drop-in filter. ECT off. 39 psi air pressure.

 

Nice! 5 speed or auto?

 

6 speed Auto

 

My 2006 automatic is at 2100 rpm doing 65 mph in top gear, according to the tach. Not sure about the 2nd gen manuals but your overall top gear ratio is shorter than mine.

If you get larger tires, I think the biggest impact will be greater rotating mass (takes more power to move heaver tires, this applies on accel and decel). If you plan to use the truck in the same way, and the current size tires have served you well, I would stick with the same size. I am going up one size next time (from 215/70-15 to 225/70-15) only for cosmetic reasons -- the wheel wells on my 5-lug are huge and they make the tires look like rollerskate wheels. This is the one vanity I am allowing myself with this truck.

About air resistance, I understand that the wind resistance increases exponentially for speeds above 60 mph. That's why high powered cars need 100hp more to go 5mph faster when they are at 220mph. My Tacoma only needs what, an additional 10hp to get from 55 to 60mph? Something like that... you guys get my point.

 

26.13 best I ever got, stock with synthetic oils

 

Same here with my 2.7L. Maybe 2 mpg or so when all averaged out.

I just don't use my 5th gear anymore in my truck. Sick of listening to the unrelenting whining. I get on a 55 mph road and it hums along at 2600 rpm still netting 21-22 mpg. It stays more around 18 mpg on my more urban commute. Even if I get on the freeway at 70 mph and it's turning up around 3300 rpm it still beats 20 mpg.

TBH it gives me ideas if I keep this truck. Like, if I source another transmission and replace the diffs with 4.88 and keep my stock 245 tires. Then 5th gear would be virtually identical ratio to my 4th gear now. As a bonus the first three gears would have the shift points of the GD3 Fit I used to love to drive, and by shortening up 2nd gear it would get rid of no man's land and I could run MT90 again instead of 10w40.

The only thing holding me back is the thought of picking up a 4.0L DCLB and that is a strong temptation at times.

 

DGXR I think you have the right idea. I looked at different choices on the Tire Rack site. The tire weights for 205/75/15 vary from 20 to 26 pounds. The Goodyear Assurance has good specs and only weighs 20 pounds:

http://www.tirerack.com/tires/tires...75TR5AAS&vehicleSearch=false&fromCompare1=yes

If I go up to 215 width, tires get a lot heavier; many are over 30 pounds.

So I'll probably go with the Goodyear 205's even though they will look small on the truck.

EJPHI