Expected fuel economy?

[Crazychopstick]

A few years back I was averaging 16-17mpg, recorded over a 6 month time frame.

I don't drive the 4Runner nearly as much these days, but just out of curiosity, I decided to record how many miles I was getting out of a full tank.

My last fillup(about 17 gallons) netted me 181 miles of in town driving. I know that's just one fill up but at so far that means at best I'm getting 11MPG, and at worst 10mpg?

That's horrible.

It's a '97, 3.4:, 4WD, AT
I have a mild lift (2/4), 285/75/16s, and a roofrack.

Should I be expecting more out my Runner or is this the price I pay for lifting it?

[troyboy162]

is it gps corrected MPG? or just off the trip odometer?

[Crazychopstick]

Just math'd off the odo.

I should use the gps huh I guess.

[troyboy162]

yeah your probably pretty close to average after you figure that in. if the motor has good power i'd guess your good.

[Crazychopstick]

I wonder what anyone else with similar mods is getting for fuel economy.

[troyboy162]

I think there is alot of mistakes out there in calculating fuel economy and that accounts for the wide range of answers on the web. 14-17 seems the most reported for the 3.4L with tires

[Crazychopstick]

How much do you think the rack would affect it?

[Seanz0rz]

i have a similar setup, i get approx 18-22 (actual) mpg highway, and 10 (actual) mpg city


i average (75% hwy, 25% city) about 15 mpg if im real careful. if i drive like my shorts are on fire, then less than that...

[Crazychopstick]

I'm like 85% city, 10% highway, 5% finding parking.

[Lee]

How much do you think the rack would affect it?

A LOT

my mileage dropped like an atomic bomb when i put a rack on my 01

[fenrisx]

I usuallry get roughly 16-17mpg if I don't drive crazy... mainly highway (although I get stuck in rush hour on my trips home from work).

When I drove down to GA back in Feb I was able to get 23mpg on one tank.. most were around 19-21. That was long periods of highway w/ no traffic though.

[Crazychopstick]

How much do you think the rack would affect it?

A LOT

my mileage dropped like an atomic bomb when i put a rack on my 01


I figured that was a big factor. What kind of rack did you have?

Is the fairing really doing me any favors?



I usuallry get roughly 16-17mpg if I don't drive crazy... mainly highway (although I get stuck in rush hour on my trips home from work).

When I drove down to GA back in Feb I was able to get 23mpg on one tank.. most were around 19-21. That was long periods of highway w/ no traffic though.


What kind of lift and tires are you running?

[fenrisx]

I'm only running 265/75s with a 2 inch lift (PP springs). That mileage on the Georgia trip was taken from corrected GPS mileage. Most of the time I just go of the ISP though.

[p nut]

A rack isn't going to affect the MPG that much if you're just driving around the city. There is no noticeable difference with my Yakima rack on and off.

Also, "city driving" can be all over the place. If you're in the city of LA, with lots of stop/go, idling, your MPG takes a big hit, then say po-dunk town in Nebraska with flat roads and hardly any traffic. Your 33's also will net you 2-3MPG loss, on the average. So with that all taken into account, you're probably about right on.

[YotaFun]

I get a consistent 14 mpg city or highway with or without a 33" tire on a Thule rack on the roof.
My speedometer is more accurate now with the 4.30 gears over the 4.10 I had.
I chalk my mileage up to a aftermarket o2 sensor.

I am curious, what work has been done to your vehicle?
You say you don't drive it as much as you use to like I do now that my commute is 70 miles round trip.

Whats the mileage?

Have you cleaned out the Throttle Body?
Are you do for a Tune up?
Any Critters making there home in your air box?

How good is the gas your getting?
Name brand like Shell or Sunoco or is it Joe Shmo gas?
Like here, we have Wawa chain gas station convenience store who get there gas from who ever has it cheapest at the time, so sometimes you get good gas and sometimes you get bad gas I have noticed that effect my gas mileage, I was down to a consistent 12 mpg for a month...

[Marc P]

I get crap mileage....average 15-16mpg, and I drive 80% freeway.

[troyboy162]

I have an ultra guage now so i can see how crappy im doing. 13.8 mpg avg and dropping

[YotaFun]

Troy, how does the ultra guage work?
Maybe i missed it but did you have a write up on it?

[mastacox]

For what its worth, I get about 14-15 in city, and 17-18 on the hwy. I've got 33's, supercharger and URD kit with several other fixin's.

I used to get somewhat better, as high as 16-19 in city and 20-22 on the hwy, but after the top-end rebuild I richened up the mixture earlier in boost with a new AFR system, and that gave a significant hit to mileage (but a happier overall engine in boost).

:wrenchin:

[fenrisx]

Just hit 19.5mpg on my last tank.. tracking with GPS for mileage. That's 95% highway (half of which is rush hour traffic [stop/go]). Also, I went light on the skinny pedal for that. This tank is looking to be a little less than my last.

[troyboy162]

Troy, how does the ultra guage work?
Maybe i missed it but did you have a write up on it?

I like it. It has replaced my speedo and my fuel guage. Kinda stinks having to remember to tell it every time i fuel up though

[paddlenbike]

My lowest mileage comes in at 16.5 mpg--that's driving 1.5 miles everyday to work...the start/stop and short mileage are pretty hard on fuel economy. My average mixed city/highway is 17.5 to 18 and mostly highway driving is 19-20+.

Last weekend I got a little over 20 mpg driving to Tahoe with a 15' sea kayak on the roof and loaded inside for a 3-day trip, not to mention sitting in holiday weekend + Burning Man traffic. I have a 2.5-3" lift, 32" BFGs and a Yakima rack. If that extra step from 32" to 33" tires costs that much fuel, perhaps I will stick with the 265/75s (32s).

The only way I can get 10 mpg is to spend a full weekend at the dunes with my foot to the floor. For that reason I suspect you may need a tune up.

[2ndGen]

recently has been 20.2-.5mpg (280 actual miles based on 32" tires). 90 hwy and rarely any traffic, and 60mph. I have a Scangauge II, deadly accurate.

btw 177k miles now.

[slomatt]

Either my ScanGuage has lost its electronic mind or removing my roofrack made a 1-2 mpg difference in fuel economy. This weekend on a trip to the Sierras I averaged over 21 mpg on the way there and then around 21 mpg on the way back (two tanks of gas). I used to average 18-20 mpg on the highway. This is driving at 65-70 with 265/75 mud terrains and an ARB bumper. For the ~80 miles we spent on dirt I got around 15mpg.

In other news, the truck is at 99,200 miles, almost ready to join the 100k club.

- Matt

[04 Rocko Taco]

I've heard the roof racks can make a large difference in highway driving. 1-2 mpg sounds about right.

[paddlenbike]

Matt, I can't remember, what type of rack do you have? I have a Yakima setup with kayak and bike attachments on all of the time. I can't discern a difference in mileage on or off.

[slomatt]

Matt, I can't remember, what type of rack do you have? I have a Yakima setup with kayak and bike attachments on all of the time. I can't discern a difference in mileage on or off.


Ken, this was with the stock rack and cross bars. My mileage definitely dropped even more when I would have my ski rack on with 4 pairs of skis and 2 snowboards up there.

- Matt

[4x4mike]

Interesting about the factory rack. I've had my Yakima on my roof the week I got my 4Runner. I never thought it decreased my mileage considering I get decent mileage. My last trip to Bakersfield then to Santa Barbara netted me 25 mpg, loaded and with the Yakima, for an entire tank. Pulling the rack and getting 26 or 27 doesn't seem plausible.

[paddlenbike]

I have noticed a continued reduction in fuel economy over the past year or two. My truck is low mileage (odometer mileage, that is) and in-tune, but I used to get 22-23 mpg on a more regular basis. Now I'm right around 20 mpg. I looked into the issue and discovered the problem isn't my truck, rather a mess of political B.S. I will try and keep the politics out of this discussion, but we now have about 10% ethanol in most of the fuel we see at the pumps. (Fuel blenders receive a $0.45 tax credit for each gallon of ethanol that is blended with gasoline, regardless of the feedstock, so there's little incentive not to.) On October 13, 2010 the U.S. Govt granted a waiver to allow use of 15% ethanol. Energy per unit volume of ethanol is 34% lower than for gasoline, so fuel economy is reduced. People ARE noticing.

To go further, here are a few other facts about ethanol in our fuels:
Ethanol Gasoline - General Problems/Issues:

1. Water Absorption. Ethanol attracts, absorbs and holds moisture in fuel tank with increased occurrence of lean, water-diluted fuel. If you are in a humid area or some place where the temperature fluctuates you will have water in the gas. The longer it sits the more it will have.
2. Vapor lock or fuel starvation- Most common in carbureted engines, hot weather and/or at high altitude. (Ethanol increases gasoline's vapor pressure).
3. Drop in octane (after water absorption, P/S and W/C occurs).
4. Decreased fuel efficiency and mpg due to lower energy. "Based on EPA tests for all 2006 E85 models, the average fuel economy for E85 vehicles resulted 25.56% lower than unleaded gasoline."
5. Decreased life cycle of parts and engine.
6. Decreased shelf life of gasoline.

Engine/Parts Damage:

1. Wear and damage of internal engine parts.
2. Damage to metal, rubber, and plastic parts of fuel system.
3. Corrosion of metal parts in fuel system and engine.
4. Deterioration of elastomers and plastic parts.
5. Deterioration of non-metallic materials.
6. Fuel permeation through flexible fuel lines.
7. Drying, softening, stretching and/or cracking of rubber hoses,
seals and other rubber components.
8. Oxygen sensor damage.
9. Damage or premature disintegration of fuel pump.
10. Carburetor damage, including clogging.
11. Dirty and clogged fuel filters.
12. Clogging and plugging of fuel injectors.
13. Destruction of certain fiberglass fuel tanks.
14. Removal or fading of paint and varnish (both internal and external parts of engine).
15. Piston/bore failure through knock/pre-ignition.
16. Piston ring sticking.
17. Unsuitable ignition timing resulting in ignition failure.
18. Gumming-up of fuel injectors, carburetors, etc. due to release of accumulated deposits in engine from ethanol alcohol's solvent properties.

E10 Drivability Issues:

1. Engine performance problems, often simply due to lower energy of ethanol-blends.
2. Hard starting and operating difficulty.
3. Hesitation and lack of acceleration.
4. Stalling, especially at low speeds.

Source: http://www.fuel-testers.com/list_e10_engine_damage.html



And from an article I read:
"Small business owners like Dan Graff and Dave Artigas already are seeing the damaging effects of ethanol in gasoline even though it is just the E-10 formulation containing 10 percent ethanol. In Stuart, Graff's team of service technicians at Crump's Lawn Equipment Center work on maintenance and repairs for a wide variety of lawn care equipment ranging from mowers to string trimmers to edgers and more. Service technicians for both businesses work daily with machinery that has been damaged by E-10 fuel. However, the regular use of E-10 gasoline has resulted in increased maintenance and repair frequency, increased repair costs and decreased performance.

"We've measured decreases in power and fuel mileage and increases in fuel consumption since E-10 became about the only gas you can get on the street," said Artigas. Graff is even more concerned because the simple act of "misfueling" — mistakenly using E-15 fuel in a lawn mower or chain saw — could completely ruin the machine's engine.

"All the information we're being sent from manufacturers like Briggs and Stratton, Kawasaki, Honda and Echo, say their equipment simply won't run on E-15 fuel," Graff said.

The EPA's decision, labeled a partial waiver, only approves the use of E-15 fuel in 2007 model year or newer cars and light trucks. No other engines are approved for use by E-15, including outboard motors on boats, small 2-cycle and 4-cycle engines like those used in lawn equipment, off-road vehicles like ATV's, motorcycles and older model year vehicles.

Part of the problem with ethanol-blended gasoline, Graff said, is it only has a shelf life of about 30-45 days. Ethanol also absorbs moisture, even through a gas tank. What's left in the tank are a layer of water topped by a layer of ethanol with the gas floating on top.

"It causes the fuel to go stale," Graff said. "It's even worse when equipment or gas tanks are stored in a hot equipment trailer, storage shed or even one's garage that can get up to 125 degrees in the day and cool down to 80 degrees at night."

Coming out of this season's cool, dry winter Graff said an estimated 90 percent of his business was addressing fuel system issues on equipment.

"They're going to have to make adjustments slowly because cars and trucks built before 2005 really don't run well even on E-10 fuel," he said. "I have a 2005 Chevy pickup truck and I've had to replace all the fuel injectors thanks to ethanol in the fuel."

Full article here: http://www.tcpalm.com/news/2011/jun/26/new-ethanol-blended-gasoline-coming-soon-likely/

See also: http://en.wikipedia.org/wiki/Ethanol_fuel

[troyboy162]

Just revisiting this post after thinking about my MPG and some long trips I want to take soon. I found the stock MPG rating for my 96 3.4 slutomatic was 18MPG combined. Now with MT knobbies, much larger and wider contact patch, armor, high mileage motor, crappier aerodynamics, and the E10 gas Paddle is talking about (Sounds like the old New England winter gas that I'm used to)...My corrected ~14 MPG combined seems on point. Gotta pay to play I guess lol

[YotaFun]

Troy thats what I am getting now.
Consistent 14 MPG...

[Obi..]

Sheesh Avy, I don't feel so bad now about my wimpy 3.0 getting 15.5 mixed, 17hwy.

[YotaFun]

Yeah, it blows, and I have given up chasing good gas mileage in a modified truck

[Obi..]

:D "Better, Faster, Cheaper..Pick 2."??

[troyboy162]

Interesting discussion here on changing 02 sensors. Sounds like some have seen a result from a fresh sensor, but more interesting is the references to instant 3-4 mpg drop appearing to be winter gas transitions

http://www.toyota-4runner.org/3rd-gen-t4rs/104510-question-about-past-my-mileage-sucks-threads.html

[paddlenbike]

Yup, on the list of ethanol problems I discussed on page 2 of this thread, ethanol significantly increases O2 sensor replacement intervals. Here's the jist of it:

Oxygen sensors (O2) used in most of today's automotive gasoline engines are failing at an ever increasing rate. What has happened, is that a small amount Ethanol in the gasoline (gasohol) will get past the piston rings and into the motor oil. The Ethanol with agitation and heat liberates some of the phosphorus from the motor oil. This phosphorus is vaporized and sucked into the Positive Crankcase Ventilation (PCV) system and burned in the combustion chamber. This burned phosphorus on its way out the exhaust coats the O2 sensor(s) building up in layers. This phosphorus coating acts as a insulation causing the sensor to react slower than normal. The engine computer reads this slow reaction time as a failure of the sensor forcing its replacement. Note: This is the same material that coats catalytic converters causing them to go "cold" or cease to function.

LINK. (http://fuelschool.blogspot.com/2009/02/oxygen-o2-sensor-and-catalytic.html)

If you think getting another vehicle will help, think again. The only solution is fighting the increase in use of ethanol or buying an electric car.

[4x4mike]

Interesting discussion here on changing 02 sensors. Sounds like some have seen a result from a fresh sensor, but more interesting is the references to instant 3-4 mpg drop appearing to be winter gas transitions

http://www.toyota-4runner.org/3rd-gen-t4rs/104510-question-about-past-my-mileage-sucks-threads.html


My best ever tank of gas on my 3rd gen is the tank after I changed my A/F sensor. The bad sensor tripped the CEL so I replaced it. The next tank was driven freeway only and I got 25 mph for 7/8 of the tank loaded down pretty good. Only reason I filled up because we'd need to anyways and I was approaching the middle of no where.

Now it's winter and a few months later so I'm back to an avg of about 17/21. With just start up and drive to my park and ride I think it's around 14 mpg.

[YotaFun]

Since I have been DD'ing the 4Runner lately I decided to track my mileage and the gas I was using.

And to my unbelievable surprise I was getting 19 miles to the gallon combined City and Highway.

All of that and I am rolling on a set of 35s currently.

Yes I have accounted for the speedo being off, I have been using google maps and an app on my phone to track my mileage and then go from there.

My worst tank was when I was coming back from VA Christmas weekend, I got 18.5 mpg.

Also I have been running strictly 93 from the same Sunocco gas station I pass on my way to work every morning.

I believe the 93 is helping out my gas mileage

[usptwins]

according to my scangauge II, i get around 20-23mpg going about 60 on the highway, and about 13-16 around town... I know it sucks, but i look at it this way. I have over 334,742 true all original miles on my 96, 4x4, auto, 3.4l SR5 Taco and not one bit has been replaced as far as the powertrain is concerned, only fluids, and other wearable items.