How to increase gas mileage?

[MICA4R]

I'd say get a new air filter or K&N for improvement. Are you running synthetic oil?

But, on a serious note. You bought a full time 4wd V8,


17ish is great

why do you ask about synthetic oil does that make the gas mileage worse I was thinking about switching over to synthetic now that I have 45,000 miles .. please do share your experience with synthetic oil and gas thanks in advance

 

[Lineman]

In my vehicles MPG has increased by switching over to synthetic on all the oils. Engine, trans, differentials, transfer cases.. Normally .5 - 1 MPG increase from changing all. Has there been a study on this? Hard to tell, each will form their own opinion.

Fuel Economy


Does .5 - 1 MPG really matter to me? NO. I prefer to run the synthetic for peace of mind anyway.

 

[jlm6985]

A few things I've done/recommend:

- AIR FILTER - If you're not feeling to ambitious, at the very least make sure that your engine air intake filter is clean. Aside from simply replacing it with another OEM-type paper, a K&N-style oil-based filter can be dropped in instead. However, don't expect huge benefits (citation). Doing the Hydrocarbon Filter Delete modification will further improve airflow, but at the risk of potentially rendering your vehicle in violation of your state's environmental law (if they follow the CARB regulations).

- TIRES - Low tire pressure can improve acceleration as the contact patch between the vehicle and the road is increased. Higher tire pressures can improve higher top speeds and fuel economy by reducing contact patch, effectively reducing resistance to the wheel's rotation. If you are shopping for tires, there are tires that offer lower rolling resistance through the use of a harder rubber compound. This feature helps improve mpg. Note that tire tread is also important safety feature that should never be ignored.

- AIR CONDITIONING - The fan and compressor are run by the engine, effectively reducing the power available to the wheels. Even though it is summertime and hot, if you're just making a quick trip in city-driving conditions, you're better-off leaving it off and rolling down a window. As air resistance becomes a greater factor at higher speeds, roll-up the window on the highway and then turn on the a/c.

- OIL - Next time you do an oil change, use synthetic. It costs a bit more, but it is worth it. Click here for reasons why.

- SPARK PLUGS - If you have the V6 4Runner, Toyota recommends changing them every 30,000 miles. If you have the V8 4Runner, Toyota recommends changing them every 100,000 (*kinda - see page EG-167 - documentation produced for the same engine's application to the Tundra indicates they should be changed every 60,000 miles)

- AIR INTAKE - If you feel a bit more ambitious, there are quite a few cold-air intake systems out there. They mostly (I think) violate CARB regulations due to the lack of a Hydrocarbon Filter system, however if you're handy and enjoy working on your car, switching out between an intake system and the stock system shouldn't take very long (~an hour and a half) for when your car needs its annual inspection (if you're in a CARB-adopted state). They are a bit pricey, but deals can be had if you shop around - I found a K&N 63-Series kit for $200-off on Amazon. By my calculations, I've been getting around 3 mpg better/per tank (driving style varies).

- MASS AIRFLOW SENSOR - There is a sensor in your air intake that the car uses to regulate the fuel mixture in the engine. Yes, there is a filter for the air, but the sensor can still get dirty. You can find a bottle of CRC MAF Cleaner for usually under $10 at any auto parts store. Note that the sensor is extremely fragile.

- THROTTLE BODY - Carbon deposits can build up on the throttle body area. You can find a bottle of CRC Throttle Body Cleaner for usually under $10 at any auto parts store. Note that you'll have to manually manipulate the throttle body.

- SEAFOAM - I'm planning on using it this weekend, but SeaFoam is a powerful cleaner that can be introduced into the engine through the vacuum line to clean out carbon deposits built up within the engine.

- REDUCE WEIGHT - Not suggesting anything major, but I saw a significant mpg improvement after I pulled my third row seats out. If it's removable and it doesn't have to be in the car, why waste the energy hauling it around?

 

[CookieRoe]

- REDUCE WEIGHT - Not suggesting anything major, but I saw a significant mpg improvement after I pulled my third row seats out. If it's removable and it doesn't have to be in the car, why waste the energy hauling it around?

With all due respect, this is the only suggestion that has reasonable merit. The 4Runner is a HEAVY SUV, perhaps ditching the 3rd seat (if so equipped) and the spare tire (might have to get run flats, if they are available for our type of tire....... I dunno) will help, but I can't imagine by much.

Point: If you are extremely concerned about gas mileage, then consider getting rid of it. For my DD, I have a 07 Civic sedan (drive about 100 miles a day). That gets me 38-41mpg (mostly highway). For my wife (drive is about 10 miles a day) the 4Runner. Been giving her 19-22 mpg mixed driving.

How much SIGNIFICANT improvement did you get by removing the 3rd seat??

 

[jlm6985]

With all due respect, this is the only suggestion that has reasonable merit. The 4Runner is a HEAVY SUV, perhaps ditching the 3rd seat (if so equipped) and the spare tire (might have to get run flats, if they are available for our type of tire....... I dunno) will help, but I can't imagine by much.

Point: If you are extremely concerned about gas mileage, then consider getting rid of it. For my DD, I have a 07 Civic sedan (drive about 100 miles a day). That gets me 38-41mpg (mostly highway). For my wife (drive is about 10 miles a day) the 4Runner. Been giving her 19-22 mpg mixed driving.

How much SIGNIFICANT improvement did you get by removing the 3rd seat??

About 1-2 mpg average with the seats out. Those things are heavy.

ALL points are points that have merit. Nobody buys a 4Runner because it has great gas milage (well maybe compared to a Hummer), but some of us use our 4Runner as our daily driver, and if I can save a few mpg by doing a few things, by golly, I'll do them. Especially if they are easy things to do.

The argument for switching to a higher-mpg vehicle is also nice in theory. I would love to be getting hybrid or EV-like gas milage. Unfortunately the financials of it aren't so cut-and-dry. I own my 4Runner and have gone back to school. Doing so has put me on a tighter budget, one where it is hard to justify picking up a car loan. And believe me, even if you're going to be getting a used Geo Metro, prices are at a premium for fuel-efficient vehicles currently (citation).

When looking at the price per gallon, the net cost of a new car (new vehicle price-whatever I get for resale), and the EPA/DOE projected annual fuel savings (calculator available here), it still is difficult to justify switching to a new car as it would still be several years before the switch can be considered financially justifiable based on savings at the pump.

Personally, I'd rather just keep my 4Runner until the wheels fall off and do what I can do in the meantime to try for every bit of mpg increase I can get.

That being said, the golden rule to all of this is that driving style has the greatest effect of all.

EDIT: No disrespect meant to CookieRoe. I'm jealous of your Civic. :thumb3:

 

[MICA4R]

In my vehicles MPG has increased by switching over to synthetic on all the oils. Engine, trans, differentials, transfer cases.. Normally .5 - 1 MPG increase from changing all. Has there been a study on this? Hard to tell, each will form their own opinion.

Fuel Economy


Does .5 - 1 MPG really matter to me? NO. I prefer to run the synthetic for peace of mind anyway.

Thanks for the link... btw whats a carburetor? (just kidding, that must be an old website)

I'm going to move forward with pure synthetic oil changes 1x/yr and just change the filter every 6 months.


"[/color]Synthetic oils are a whole different story. There is no VI improver added so there is nothing to wear out. The actual oil molecules never wear out. You could almost use the same oil forever. The problem is that there are other additives and they do get used up. I suppose if there was a good way to keep oil clean you could just add a can of additives every 6 months and just change the filter, never changing the oil.

When the additives wear out in a synthetic oil it still has the same viscosity. It will not thin as a mineral oil. The fear that some say Porsche has that oils thin when the VII runs out is not applicable to these synthetic oils. These oils will always have the correct thickness when hot and will still be too thick at startup as with all oils of all types, regardless of the API / SAE viscosity rating."
[color:#3333FF]

 

[Jerrydog]

Jerrydog, just curious, how long have you had the K&N drop-in in your rig? Any issues? I ask because I put one in my old 3rd gen runner and about 3-4 months later it threw a CEL and it turned out to be the MAF sensor. The K&N was "leaking" a little bit of the oil on the sensor causing it to throw a CEL. It didn't damage anything, all I did was take it out and replace with an OEM air filter and cleaned the MAF sensor good.

I, like a lot of V8 owners, are always looking for ways to improve fuel economy. However, it's so dang difficult when you hear that V8 growl by punching it

I used the stock replacement style K&N filter, been in there a few 3-4 months. I had cone style on my Pathfinder for years with no issue, I did have a problem with one on my old 94 civic, it was giving off lint that clogged the screen in front of the mass air unit, called K&N and they sent me a new one and had no trouble after that.

I suspect if the filter is too wet with oil it could certainly cause the problem you mention....

 

[Jerrydog]

I still don't buy the HFC mod, in all the posts in that thread there is still no Dyno comparison, flow test, or anything but the owner's butt dyno. I just don't see that HFC creating that much of an improvement with such little data... Don't get me started on "High Flow" filters, that debate is a long one as well.

As stated earlier, any mpg gain below about 3 mpg us just not going to be cost effective and probably end up either as a debt or harm the engine.

Im going by toyota's meter on the dash, before 18.5 now 20.5 same commute, same driver, same couple of gas stations, same synthetic oil, same tires.....Its not dyno scientific but the fact remains the numbers changed after I chaged two things, removed the HCF and installed a K&N filter....

Some quick math, not 100% accurate because costs change etc but:

15,000 mile per year at 18.5 miles per gallon at 3.75 per gallon gives you $3040 for gas.
15,000 mile per year at 20.5 miles per gallon at 3.75 per gallon gives you $2744 for gas

Cost differance is $296.00 saved. Cost of K&N filter $58.00 total savings first year $238.00 for 2 mpg increase....

Since i ran the same K&N cone filter on my 97 nissan pathfinder its entire life, I can 100% say it did not affect engine life as I got 300k miles out of it and it didn't even burn oil, only leaked it.

Im going with my Butt dyno on this one.

 

[Eastcoastrunner]

ive always heard that it is a bad idea to switch from reg oil to synthetic after a vehicle has been driven significant mileage...

 

[Nuke]

I still challenge ANYONE to PROVE that a drop-in High flow (and even a CAI, for that matter) improves fuel mileage. And as stated earlier, unless your "experiment" involves your own 500 gallon stock of fuel, any numbers you post are meaningless. So those that have posted $$ payback #'s, yeah, right. :rockthrow:

Synthetic oil vs dino oil: good luck there, too.

 

[Jerrydog]

I still challenge ANYONE to PROVE that a drop-in High flow (and even a CAI, for that matter) improves fuel mileage. And as stated earlier, unless your "experiment" involves your own 500 gallon stock of fuel, any numbers you post are meaningless. So those that have posted $$ payback #'s, yeah, right. :rockthrow:

Synthetic oil vs dino oil: good luck there, too.

LOL @ YOU!

So if you did to your truck what I did to mine and the numbers changed by 2 points you would just consider than an annomoly?

Please enlighten us why the numbers changed.

 

[Nuke]

For 2 years I drove the same, one-way, 410 mile stretch of roads every 2 weeks round trip and bought fuel from the same gas stations along that route. Without having made any mods to my vehicle, cruising at the same cruise control settings, keeping track of winds, temps, humidity, etc., being sure my cold tire pressures were the same each trip and my mileage would vary by up to 4 MPG difference, hand calculated (the error-laden on-board was also indicating an equivalent difference) and on a few occasions, more. The variable was primarily the fuel's ethanol (and lord knows what else) content. There were some other variations due to wind speeds and direction and lesser changes due to temp and humidity but overall, you're not going to have convincing data unless you resolve the fuel variance (tough to do without having your own, single stock) and factor in the temperature, humidty and wind impacts; another toughie.

I'm not saying that doing a half dozen "things" to our engines won't increase fuel mileage, just that it's darn near impossible to accurately record. Multiple data points under the same conditions are ideal. Unfortunately, we rarely if ever get those opportunities.

Let's even SAY that synthetic gets you 1 more MPG. Unless you decide to use synthetic for it's TRUE advantages and that would be oil change frequencies of 10,000 miles or more (equating typically to 3 times that of dino oil to offset the 3X the price), then you're losing money for that 1 MPG gain.

Let's say that drop-in oiled filter gains you 1 more MPG. Every xx miles (15k-20k miles is when I used to clean and reoil mine) you're drop-in has to be cleaned, dried and reoiled so your need a 24 hour replacement if you need to drive the T4R. Also, that's a bottle of filter oil plus your time. Have you actually gained after that's said and done? Pennies, perhaps.

Let's face it. You want to save money on fuel? Change your driving habits.

 

[SMEE]

I can't believe no one has mentionted this yet: Use ethanol free gasoline!!! I've been using it for the last 5 or so fill-ups, and I consistently get an avg 20.5 mpg! Thats what the Toyota dash computer says day in and day out. If I have to accelerate very quickly, it temporarily goes down to say, 20 mpg, but it returns within 10 miles or so. It also helps that I don't drive like a maniac and usually try to keep the RPM's under 2k. I have the '06 v8 so keeping it under 2k is very possible, all the time. Go to Ethanol-free gas stations in the U.S. and Canada and type in your zip-code to locate a provider near you. Note: here in Oxford, MS, the price of this gas is $.05 above the price for gas with ethanol. Finally....with a 20 gallon fill up, it costs me an extra dollar, but i get 4+ additional miles per gallon! The higher price pays for itself with my extra mpg's!!! Oh yeah, and the added horsepower is wonderful.

 

[Nuke]

+1 for ethanol-free gas. Great IF you can find it, unlike me.

 

[Edubsam]

First of all, it doesn't matter what you think has an effect or not. The fact is that even a 1 mpg increase will add up over time and save you cash. If you can do something, regardless of what it is, to help (and the price isn't huge) go for it.

Just something no one else has added: I had a snowboard rack on my Subaru and the resistance dropped my mpg by about 1. If you have anything mounted on the roof you don't need, sell it or take it off until you need it.

 

[MICA4R]

For the most part, any mod you spend $$ on to improve gas mileage has either ZERO payback or the payback will take years. If you're that worried about your fuel costs, then you'll probably do better packing a lunch instead of buying those Happy Meals, brewing your own coffee instead of buying Starbucks, drink water instead of soda, yada-yada-yada, and put that savings towards your fuel budget.

Sorry, guys, but the entire "improving gas mileage" debate is virtually useless beyond 1-2 MPG. Improve your driving habits and keep your vehicle maintained. And since the fuel you buy, even from the same gas station, could have a varying ethanol content from 0 to over the stated 10%, trying to determine your REAL AVERAGE fuel mileage change due to a mod is nearly impossible. You'd need to buy about 500 gallons of the same fuel and THEN do your "experiment".

But mods are sooo much fun! What about the Utility of "satisfaction" "happiness" " sense of accomplishment" ?

Now - a - days everything in society and life is so easy and packaged for quick consumption and then trash it... its kinda fun to fix or do a little mod here and there.

Not like back in the day... when we actually had to work on our cars to keep them running =)

 

[Nuke]

Don't get me wrong; I love to tinker and try different things. I have mods.

But when you consider the variables, trying to ACCURATELY MEASURE gains or losses is virtually useless. If you can sift through the variables, gains or losses due to different mods or fuel system cleanings or different oils, plugs, etc has to be a "gut" thing; You could conceivably install that CAI and gain 2 MPG but if you just filled up with fuel from some azzhole station that has over 10% ethanol after using near-zero ethanol fuel, you'll likely see a net loss and attribute that to the CAI or just the opposite; have an actual 2 MPG loss but filled up with ethanol-free fuel and think you have no gain OR loss.

:boxer:

 

[PaulB-2006 T4R]

I can't believe no one has mentionted this yet: Use ethanol free gasoline!!! I've been using it for the last 5 or so fill-ups, and I consistently get an avg 20.5 mpg! Thats what the Toyota dash computer says day in and day out. If I have to accelerate very quickly, it temporarily goes down to say, 20 mpg, but it returns within 10 miles or so. It also helps that I don't drive like a maniac and usually try to keep the RPM's under 2k. I have the '06 v8 so keeping it under 2k is very possible, all the time. Go to Ethanol-free gas stations in the U.S. and Canada and type in your zip-code to locate a provider near you. Note: here in Oxford, MS, the price of this gas is $.05 above the price for gas with ethanol. Finally....with a 20 gallon fill up, it costs me an extra dollar, but i get 4+ additional miles per gallon! The higher price pays for itself with my extra mpg's!!! Oh yeah, and the added horsepower is wonderful.

Amen!

Here in MN there are very few stations with non ethanol gas and the pumps that have it have a warning about only using the gas if you have a collector car or in a small engine like a lawn mower. The gas is usually $0.20 higher than high octane gas.

 

[BlackWorksInc]

I think a lot of people are confusing what me and some of the other members are trying to point out.

There are so many variables in trying to accurately determine fuel efficiency that a gain of +/- 3~4 MPG could be attributed to any single or combination of factors. Without a control vehicle (Which in reality would either have to be a fresh from the factory or rebuilt vehicle to attempt to eliminate ANY wear-tear, clearance changes, and/or material issues.), a controlled fuel source, and controlled driving conditions you CANNOT accurately determine fuel economy. Even in "real world" driving conditions, the amount of variables you have to account for result in a time base far too large to really see a gain more than say 3~5mpg. Think about it this way, if you just dropped in a CAI Filter or "Hi-Flo" filter, do you really gain 2~4hp? Or is it because your old filter was kind of clogged, the gas wasn't that good, and now you're throttling it more?

All I am trying to say is that while its great that people are experimenting and trying to get what they can out of their vehicles, you cannot take it as gospel. Just because it helped out Joe-Shmo's 4Runner for a supposed boost of 2mpg, it will probably not work for you. Gotta take it all with a grain of salt.

PS- Your Fuel Economy gauge is off because it is calculating fuel based on a roughly under full tank, if you check the information in your owner's manual you will see that Toyota outright states that the fuel mileage computer calculates your "Miles to Empty" value based on a less than full tank, so that by the time you Fuel Low Light illuminates you're already empty in the computer's eyes while you probably have another gallon or two to go. Hence why there seems to be a small discrepancy with your fuel readings.

I'm not a 100% sure what its algorithm is, but maybe I can look it up on TIS later today when it slows down at work.

 

[Nuke]

I think a lot of people are confusing what me and some of the other members are trying to point out.

There are so many variables in trying to accurately determine fuel efficiency that a gain of +/- 3~4 MPG could be attributed to any single or combination of factors. Without a control vehicle (Which in reality would either have to be a fresh from the factory or rebuilt vehicle to attempt to eliminate ANY wear-tear, clearance changes, and/or material issues.), a controlled fuel source, and controlled driving conditions you CANNOT accurately determine fuel economy. Even in "real world" driving conditions, the amount of variables you have to account for result in a time base far too large to really see a gain more than say 3~5mpg...

You've essentially validated what I've been saying...