Bob_98SR5

Guys,

My mpg on my new 32" Revos shows that I only got 16.4 mpg vs. my average 19-20 mpg on my stock 265/70/16 Goodyear RTS's. Also, I'm sure that the new sound deadening contributed to the loss of mpg but 3-4 mpg?!? I don't think that would've effected it that much.

So I gotta get my mileage up. So from my recollection, there are several ways to increase mpg:

1) Inflate tire pressure to higher inflation range (more tire wear though)
2) Install a new free-flow muffler (1 mpg)
3) Taurus fan (1 mpg-ish according to the Ford article)
4) Cleaning out throttle body
5) Replacing O2 sensor(s)

Any other mods to increase mileage? I don't think the ISR mod does anything positive for mileage and even if it did, I wouldn't want it b/c of the loudness.

Thanks,
Bob

BT17R

Bob, slow down! Nah, I don't think much will help, but here's what I do that usually returns 1-2 mpg:

-synthetic oil (0W-30)
-premium fuel (for full spark advance and power)
-leave the spare tire, jack and tool kit home (Fix-A-Flat)
-remove running boards
-run < half-full fuel (Chevron works best for me)
-front aligned to 0° toe

You might also consider:

-remove hitch assembly
-replace air filter w/OEM (elimate "wet" filter effects on MAF)
-run a can or two of Techron through
-replace plugs (big grain of salt here considering the effort)

If you're really desperate, remove all the Thule stuff. The aero drag from racks and lights is substantial.

PhxTRDRunner

add:

-buy honda civic
-leave gas guzzling 4runner at home
-walk
-ride bike



LOL, those are the only options I found worth a darn, however, I did get better gas mileage when I added the SC and drove like a human. I think you have all of the basic's covered though!!

L33T35T 4Runner

do i hear a 4x4 conversion coming on?

4RUNR

I think his goal was fuel economy, not getting more MPG I went to the 4Runner from a very good MPG sedan that needed premium, but regular in 4Runner actually turns out to be less expensive to fill up mile for mile.

When sitting down and doing the number it all comes into perspective, that a few MPG is nothing to worry about.

Take the deck plate mod (or ISR), say it costs $15 total for all odds and ends. Now, *if* the mod yielded a very optimistic 1mpg improvement think how long it would take just to break even.

Lets take a base 19mpg and say $1.50 per gallon. That works out to be 7.895 cents per mile. Now take 20mpg, 7.5 cents. A savings of exactly 0.395 cents per mile. Take 1500 cents of the mod cost, divide by 0.395. You'd have to drive 3797 miles before breaking even, or about third to half a year. So in a year of driving you'd have $15 more in your pocket, factor in time value of money and it's almost not worth it if not for the 'fun factor' of modding.

Now if you go from 19mpg to 16mpg at the $1.50 gallon mark, you are losing roughly 1.5 cents per mile. Now figure most people drive about 200 miles a week, that's a whopping total of $3! About what a can of pepsi and a snickers bar would run. Nothing to really even think about. Feel better now?

TDiddy

Hey Bob,

Replacing an O2 sensor helped me because I had a bad one. Unless you have a faulty sensor (CE light), then replacing them won't get you anywhere on mpg gains.

BT17R

4RUNR, will you be my tax accountant?

Yeah, the premium fuel for full advance and power means more efficient operation for a given throttle opening. Less throttle for the same power compared to running a lower grade fuel will return better MPG. Theoretical if the engine is designed for 87 to begin with, but in the engines with "Premium Fuel Recommended" (vs. required) advisories, I'll get better economy with premium. The extra power doesn't hurt, either.

Oh yeah, the '04 Prius (mine's due early October) is rumored to be rated ~55-60 mpg on Regular, even with the newly tuned 12:1 CR IC engine part of the hybrid system.

Glenn

How are you calculating your mileage? When you put bigger tires on without changing the gearing, it will throw the speedometer and odometer off.

When I went to larger tires, I did regear at the same time. My speedometer and odometer were still off though. I fixed that with an adapter on my speedometer cable.

For an accurate way to measure your mileage, you might need a different way to measure how far you have gone other than your odometer. GPS is what I use, and it's highly accurate.

4RUNR

Do you really want me to be if I call ~$600 loss in mileage on top of ~$550 cost of tires nothing to think about? (There's another perspective: if the tires last about 40k miles * 1.5 cents = $600, more than the tires themselves. Now if that 600 went into 401k with say 1 to 3 dollar match from the company, or any other opportunity cost, the big tires become a pretty expensive proposition)

Now if the tires are really ~31.8 high, vs. ~30.7 stock that’s about 99.903" and 96.447" respectively travel distance per revolution, or ~3.5% difference. The lows of 19mpg and 16.4 are 13.7% apart so it's still roughly a 10% loss in MPG even if no correction was made initially.

mtnfreak

Bob - unless you're putting a heckuva lota miles on the Runner or gas prices really jump, the fuel you'll save from these mods won't match the money you've poured into it for a long time. The best advice I can give you is 1) don't be a lead-foot and 2) get a bike. Other cheap advice is to not carry what you don't need right then (including the Thule set up).

Bob_98SR5

DOH! Boy, did I forget that one. You are absolutely right on this point.

And to the rest of you: all good points. Time to dust off the bike and ride 15 miles to work! Actually, the commander-in-chief and i decided to carpool as her work is on the way to my work. While that won't improve my situation, it'll definitely save on gas.

Bob

mtnfreak

Of course, you may not want to know. Kinda sucks to find out your Odo. is only off by like 2% and the rest of the difference is from more rubber hitting the pavement.

4RUNR

The spare wheels does weight a ton. I just took mine off, as I simply don't ever see changing it in a tie on the drive to or from work, so it's a waste. A brand spanking new Bridgestone on a 16" steelie was 70lb! A GoodYear on aluminum 16" 60lb. With the factory hitch on, and spare off, the rear end came up half in inch higher! Probably would be 1" without hitch. Free lift

sschaefer3

You know the ONLY thing that is going to "really" work is 4.56 gears, assumeing you have 4.10's

You'll be back to your original milage. Most places will not want to do a 1 ring jump though and your looking at $1100 to $1700.

Toyota Punk

I just compared my mileage from the last tank to the one before when I got gas yesterday. Last tank I got 16.4 mpg with the ETC on roughly half the time, midgrade fuel and moderate to heavy A/C use. This tank yielded 19.6 with next to no A/C or ETC use and less spirited driving! That's a pretty huge difference, and I couldn't believe it. It really makes a difference how you drive and how much you use things like A/C and ETC power.

Now... I think I'm going to take off my spare also, sounds like a nice idea!

mkool

I will try...take my spare off and drive around today. hehe~

L33T35T 4Runner

Fix-A-Flat doesnt repair tires shreadding

also.. i can tell you from a tire mechanics point of view, that stuff is NASTY. dont ever bring your tires to me if you have that stuff in there. i HATE fix-a-flat. it gets everywhere, stains everything, and is very toxic

TDiddy

I agree, the speedo/odo difference is not really off enough to make a big difference in mileage calculations.

Poul D'eau

I've noticed about 20 more miles on a tank of gas. The only thing I can figure out that could have made the improvement is that texaco is now owned by shell. (makes me wonder what texaco was passing off as fuel)

Shell has a tv spot talking about better MPG and they are not lying.

My mom noticed it in her camry as well.

Paul H.

I id the air box mod, removed the elbow, and cleaned the throttle body and my gas milage on a recent trip to Maine averaged 16 mpg with a/c on and 19 mpg without while in Maine. I also ran some fuel cleaner through at the start of the trip. Other than getting something like a Rav4, I don't know what to do to get better milage, especially during the summer. By the way, I would never leave home without a spare. you never know when your tire will go flat. Fix-a-flat will not repair large gashes.