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2002 Silverado 1500 2wd

Ropez

By Ropez
in Towing, Hauling & Hitches

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Ropez New Member

Ropez

Posted
Posted

I'm new in this site but sometime I read w what you post

I have a 2002 Silverado 1500 4 door ls 5.3l engine with 4 speed transmission with 20" wheels, I drive 60 miles everyday, the truck run good but but it's very hard in gas, only 14 mpg combined and when I pulling my trailer is only 11, when i go at 2000 rpm and the speed is 65 m/h but i really go 72, i know because my wife drive her car at the same time i drive mine and that is her speed

My question is, what can i do to increase the mpg but at the same time have torque?, i don't know what is my ratio, do you think that hydrogen generator or gas vapor will work and increase the mpg?

Thank you

mike221 Enthusiast

mike221

Posted
Posted

I wish my 2500hd got 11 while pulling a trailer.. I get 10 unloaded, going downhill, with the wind to my back.

 

In response to the speedo thing, you will want to get your truck reprogrammed to match the new tire size if you want the speedo to work properly. I'd be willing to bet its still calibrated for the oe tire size. As a general rule, more emissions equipment never helps anything. Your best bet is to get it tuned, put an intake and exhaust system on, and go back to the oe wheel and tire sizes

 

 

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mike221 Enthusiast

mike221

Posted
Posted

Also, look at your tires. Check tire pressure, alignment, etc... Are you running A/Ts or street tires? If you never go off-road, I'd recommend running street tires instead of all terrains. As for determining gear ratio, look in your glove box. There should be a sticker that has a bunch of 3-digit codes on it (G80, etc...). I'm not sure what the gear ratio codes are, but you can google them fairly easily. In fact I'm pretty sure there's a thread on here about it.

 

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mike221 Enthusiast

mike221

Posted
Posted

In the end, don't expect anywhere upwards of 20 mpg. Not in a 2002 half ton with a V8. You can make minute improvements here and there, but 14 combined is still pretty damn good for it. Also, watch how you drive. Don't hot rod the truck every chance you get. Feather into acceleration, coast more before applying the brakes, etc...

 

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Ropez New Member

Ropez

Posted
  • Author
Posted

Thank you for your comments

I already have an air intake installed and a chambered muffler but that doesn't help to much, do you know if another transmission is compatible?, what about hho generator?

sahls01gmc Senior Enthusiast

sahls01gmc

Posted
Posted

If you're looking at installing a generator to increase your mpg, I think that you should start looking at a new truck instead. New ones get close to 20mpg's all day long....

oldscsc Enthusiast

oldscsc

Posted
Posted

Two main things here. First is your speedometer. When you install taller tires, your speedometer will read slower than you are actually traveling. Your odometer will subsequently be incorrect, and hand calculating MPG will be off (lower) than the actual number your pickup is getting.

 

Second is the wheels and tires. When you installed the 20s, you did two things: greatly increased the unsprung weight at each corner of the pickup, and effectively raised (lower numerically) your differential ratio. That means less torque multiplication. I'm willing to bet neither of these things are helping your fuel consumption.

 

My suggestions:

1. Skip the gimmicky fuel economy improvers.

2. Swap the 20s out for stock (or similar) 16s. The smaller and lighter the tire, the better MPG you'll get.

3. If you keep the 20s, get the speedometer reprogrammed so you can judge actual MPG.

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