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Discussion Starter #1
ive been researching throttle body spacers and gear and stuff like that cause i have stock gear and 31s which isnt that big of a tire but it is killing the gas mileage enough whats the best bang for the buck on picking up the most amount of fuel mileage for my 2.8
 

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Throttle body spacers are a waste of money

Start with intake, exhaust, Denso IR plugs and eFan. Once done with that get a tune done.

If you have 31s with no adjusting of the PCM....your speedo and odometer are off and you wont know your actual mileage
 

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What kind of fuel mileage are you getting? I got 22 to 24 when my Z71 5 Cylinder was running 31's. I regularly get 17 to 19 with 32's. I am tuned, and have a header and 3.42 gears.
 

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ive been researching throttle body spacers and gear and stuff like that cause i have stock gear and 31s which isnt that big of a tire but it is killing the gas mileage enough whats the best bang for the buck on picking up the most amount of fuel mileage for my 2.8
31x10.5 may not be THAT big of a tire. However look at how much of an increase over stock it is. Your computer is programmed to run factory size.

I am willing to bet you have increased by 11% with an assumption you have 225/75-15 stock tires. Paired with what is probably a high gear ratio and a small motor it all adds up to significant power loss.

If you aren't financially prepared to do the other work that was suggested, you can probably see gains with just a tune. If nothing else, have the shift points programmed to match your tire size. It's probably shifting at all the wrong times. My truck has ~10% larger tires and my shift points are incorrect as a result. I at least have better (assumed) gearing and more engine.
 

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Throttle body spacers are a waste of money

Start with intake, exhaust, Denso IR plugs and eFan. Once done with that get a tune done.

If you have 31s with no adjusting of the PCM....your speedo and odometer are off and you wont know your actual mileage

This. I used to be in the same situation, running 33s on stock tune and gears. Speedo was somewhere around 25% off. Really fucked up mileage readings. There's a tire size calculator on a tacoma forum somewhere that can show you the % off your speedo is based off stock and current tire size.


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25%? How the heck did that happen? Did you change gears AND tires? Speedometer inaccuracy is equal to difference in tire percentage.
 

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Discussion Starter #8
thanks guys i really needed to know that. where exactly can i get a tune and how much. as for exuast idk if it hurts or not but i cut my cats and stuff off and left it that way cause it doesnt sound bad it sounds mean.
 

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@limequat limeswap tunes. @Supermodulation does tuning. and a few other members and sponsors all do mail order tunes and/or road tunes.

You could also go to a local shop and get a dyno tune.
 

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@limequat limeswap tunes. @Supermodulation does tuning. and a few other members and sponsors all do mail order tunes and/or road tunes.

You could also go to a local shop and get a dyno tune.
thanks ill see if i can get them to send me a tune and how much and all cause i went to Louisiana to see my sister a couple weeks ago and with them running 80-85 the whole way down there i only got 16 which i guess is ok just seeing if i can pick up a lil
 

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You only got 16 because of running 80 to 85. Anything above 75 mph these trucks drink gas, I get 17.5 to 18 running at 75 mph, drops to 15 at 80 mph.
 

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2005 Chevrolet Colorado/ 2018 GMC Canyon
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I have a 2.8 with 31s with 3.73 rear and average 21-23 mpg @75mph. Also have the same lift as you do.
I have done several things to my truck.
Supermod Efan
Supermod supers parks
93 octane tune
Mbrp exhaust
Gutted primary cat
Volant intake

The best "bang for your buck" would be the tune. But if you want to add other engine modifications, you need to do those first before the tune to get the most out of them.





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Discussion Starter #13
I have a 2.8 with 31s with 3.73 rear and average 21-23 mpg @75mph. Also have the same lift as you do.
I have done several things to my truck.
Supermod Efan
Supermod supers parks
93 octane tune
Mbrp exhaust
Gutted primary cat
Volant intake

The best "bang for your buck" would be the tune. But if you want to add other engine modifications, you need to do those first before the tune to get the most out of them.





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im thinking gear would be first cause a stock gear for my truck is like what a 3.42 or something close to that?
 

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thanks ill see if i can get them to send me a tune and how much and all cause i went to Louisiana to see my sister a couple weeks ago and with them running 80-85 the whole way down there i only got 16 which i guess is ok just seeing if i can pick up a lil
On the highway I can get 20-21 out of mine with +10% larger tires. I'd probably also get 16mpg if I raced at 85. I try not to drive much over 75 for long trips. Most speed limits where I go are 70, so barely over that keeps me out of the way of traffic and nets me decent economy.
Get yourself a lighter pair of shoes and you're mileage will increase.

As for local tune, ask around some of the shops if they do, or know of anybody who uses HP Tuners. They can then tell you the cost. I was quoted well over $200 to get started on mine. The guy didn't have any credits to get into the system, it requires 2 credits at $75/ea, so right off the bat I'd be paying $150 for the credits to allow the software to talk to my PCM. He was just an independent dude who did this in his home garage on the side. Somebody who does it often may have 'money in the bank' and can get into yours for cheaper.

Also take into consideration that 2wd Z71's are tuned differently than yours, so those individuals will see less harmful performance effects with the same size tire as you.

Good luck.
 
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