Help with poor gas mileage! 96 SR5

[03V84R]

I recently purchased a sweet 96 SR5, mileage is at 157K. Timing belt and new radiator 2 years ago. Truck was built for the trails. Sonoran 1.2 lift, welded sliders, 1" body lift, Savage Offroad armor, 265x75x16's Firestone Destinations MT's, mounted on OEM Tundra wheels, front and rear extended diff breathers, etc.. I added an ARB front bumper, cleaned the throttle body, POR-15 the chassis, installed new rear brakes, seafoamed her. I love the truck but cant get better than 16MPG HWY. MPGs really go down when driving in 4WD.

I love the truck but was hoping to get better mileage. Am I delusional? I have a new set of plugs to go in. Guess last resort would be a new upstream O2 sensor.

Would removing the skids(very heavy), switching to AT tires, lowering the truck make a substantial difference?

Any thoughts? Ready to sell he and switch back to a 4th gen.

 

[UnderFire]

Lifted, extra weight, heavier tires. You're doing good at 16 MPG, a 4th gen will get the same. There's a common myth that some people perpetuate that these trucks stock or even modified can pull low 20's easily, that's just not true. Expect 12-18 MPG depending on weight, drive train, added wind resistance etc.

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[phattyduck]

First... A 4WD V6 auto is rated 15 city / 18 highway / 16 combined. Keep that in mind.

A few questions:

- Do you have a roof rack or other aftermarket parts that ruin what little aerodynamics the truck has?
- How fast do you drive when you are on the freeway?
- What tire pressures do you run on the street?

You CAN get over 20mpg if you keep the speeds around 65 mph and there aren't winds or significant hills... and maybe you get a bit of drafting help from traffic around you.

Also, your tire size will make you underestimate your MPG by about 7%, which makes 15mpg uncorrected 16mpg corrected.

-Charlie

 

[BoomerBob]

On my 98 I run A/T LT31/10.50R15 109R tires and get 16 combined mpg; probably 18 on the highway. On my 01 I run the stock size and get a combined 20 mpg so probably 22 on highway trips if I keep it around 75 mph or under. The 01 is stock and not lifted.

 

[phattyduck]

On my 98 I run A/T LT31/10.50R15 109R tires and get 16 combined mpg; probably 18 on the highway. On my 01 I run the stock size and get a combined 20 mpg so probably 22 on highway trips if I keep it around 75 mph or under. The 01 is stock and not lifted.

4WD costs around 2mpg on the highway, even when not in use. My 4Runner when it had the stock 15" wheels and small tires and 2WD got around 24mpg highway for the first 150k miles, though that was at 65-67mph.

-Charlie

 

[gamefreakgc]

You are doing great actually for a heavy, lifted vehicle. When you lift it more air passes under the vehicle which kills gas mileage in a hurry.

I've tried all the tricks that I know of. Reducing weight in the back (took out my tools) no extra roof racks or accessories, I have H/T tires on there too now. Changed the spark plugs, wires and other spark & fuel components. Switched to full synthetic oil and synthetic transmission fluid. High flow air filter. I am still stuck at 15-16 MPG's, mostly city driving. On road trips at 70 MPH I can get up to 19 MPG's, sometimes. On non-ethanol fuel though I did a trip through Oregon on 21 MPG's. Toyota didn't leave any room for improvement for MPG's like they did on the 2nd Gens.

The last thing to try is a bigger exhaust though I doubt it will do much. On my 91 Pickup, a bigger cat-back exhaust netted me +1.5 MPG's but I haven't heard of the same success on 3rd Gens.

 

[03V84R]

Figured as much. I am running 3 Thule roof bars with a ski rack for my fishing poles. I know my speedometer/odometer are slightly off. I dont push it, I set the cruise at 60mph on the hwy. 4WD is soft sand beach driving= lots of resistance. Guess it is what it is. Thanks for the support.

 

[jgue467]

Yeah you've done at least 6 significant upgrades that each can sometimes detract 1/2 mpg, so still getting 16 on hwy is Pretty Good! Enjoy the Runner. :cowboy:

 

[Outrider]

I agree with most of the points above. 16 is about what I would expect with your rig.

20+ on the highway is not out of question, with a 2WD.

I recently got 23. I have gotten 23.5 on a 400 mile trip, setting the cruise control at 60. 65 is the magic number on these, as a balance between covering ground and getting good mileage. Anything above 65, and fuel economy goes down very rapidly.

I normally get 18.5 - 20 around town, without heavy acceleration.

 

[photoleif]

my best is 26, a surprising anomaly with a tank spent on mostly flat terrain at 55 mph on a calm day. generally i'm getting 19.5-22 (calculated) so long as i'm not doing a lot of stop-and-go city driving and keep it under 65 on highways (no interstate near here so that's generally not a problem). i've got new plugs, wires, full syn for all fluids, stock bumpers, no rack, and 265/75-R17. efficiency definitely drops at 75, down to the 17mpg doldrums. air resistance at 75 is nearly double that at 55 (around 1.8x). obviously that doesn't translate to half gas mileage but it's suggestive of the issues with heavy use of the skinny pedal.

 

[plcfcng]

I have a 2001 with a 3.4 I built a 97 with a 3.4 I get 20 to 21 on the freeway usual driving about 75 mph in my 2001. The 97 gets about 18 mph they are both 2 wd running highway tires. When I drove the 97 I found the rpm was higher at the same speed as my 2001.
:dancin:

 

[UnderFire]

4WD costs around 2mpg on the highway, even when not in use. My 4Runner when it had the stock 15" wheels and small tires and 2WD got around 24mpg highway for the first 150k miles, though that was at 65-67mph.



-Charlie

The 4WD hasn't made much of a noticeable difference in MPG that I've noticed. I went from the standard Add hub setup to the manual lockouts which essentially emulate a 2wd where only the hub is spinning on either side and no improvement was made.

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[Rolling_Thunder]

I recently drove from FL to southern CA (I-10) and I averaged right around 22.5mpg - I was driving 70-85mph almost the whole time (especially west TX)

My 4Runner is a 98 that was originally a 3.4 auto and 2WD - I converted it to a 3.4 4WD with a 5-speed. I swapped on 265/75/16s on aftermarket american racing wheels with a little 2" list. no armor --
I was also carrying about 500lbs of crap in my truck that trip .... It's possible

 

[photoleif]

I recently drove from FL to southern CA (I-10) and I averaged right around 22.5mpg - I was driving 70-85mph almost the whole time (especially west TX)

wow, what's your special sauce for MPG? that's super at 70+. nice work.

 

[Rolling_Thunder]

wow, what's your special sauce for MPG? that's super at 70+. nice work.

I've discovered that driving habits play a big part of it. I'm just super easy going these days so I am rarely in a rush

compared to that it's just the set up I described before - I did a basic tune up before the trek - spark plugs, plug wires, air filter, oil change and that's it.

Oh I forgot to mention my 4Runner has the factory 4.10 gears

 

[feta]

I saw 1-2 MPG increase when I replaced upstream o2 sensor. 19ish city driving

99, 5sp, 4wd, 265/75/16, heavy load in back, 130k miles

 

[phattyduck]

wow, what's your special sauce for MPG? that's super at 70+. nice work.

5-speed with 4:10 gears. Auto hurts mileage.

-Charlie

 

[Rolling_Thunder]

5-speed with 4:10 gears. Auto hurts mileage.

-Charlie

Yep - the overdrive ratio in the auto is better but the auto still gets worse mileage.

 

[jross20]

Nonsense, you can get more than 16. Key is to keep the rpm's under 2k. Don't drive faster than 55 mph. Learn to control your acceleration. NEVER accelerate uphill unless it is an emergency. NEVER use drive through's or do any idling unless it is a traffic light. These items alone take me from 17 to 20.

Some people think it's crazy, but I've achieved 28 mpg in a 2wd 2nd gen Tacoma. That was with a 3" lift. Based on my experience with the 3rd gen 4runners, 18 mpg with some armor is totally realistic. Of course you loose it all during 4wd sessions.
Currently I've been researching tires to ensure I get the best combination of tread and low weight.

So again, learn to control your pedal foot and you can bring it back up.