Aweful fuel mileage

[skylark]

My 98 got 14.6 highway empty on a 5 hour trip and 12.2 on the way back pulling a mastercraft ski boat. I have 4.10s, 35s, and a 5 speed. If its worse than that, you may need to be concerned. That is corrected mpg also, my speedometer/odometer is off ALOT from the tire size.

Your also using a nv4500 not a power sucking 4L80E.

 

[96k2500chevy]

Yea just wanting it to get somewhat better. Gonna do a cold air intake and throttle body spacer with new dual exaust and see if that helps

 

[great white]

Wasting your money if you're chasing mpg.

higher final ratio is where you want to spend your money for mpg in your particular truck.

However, if I were you, I wouldn't waste my cash on it.

The most you'll squeeze out of it on a good day is 15-16 mpg. That's with an engine and transmission in good shape (IE: not a 150-200,000+ mile vehicle), the rest of the vehicle in top shape, driven properly and in favorable weather/road conditions.

Changing the gearing will run you anywhere from 700-1000 bucks, maybe more. That buys a lot of gas to cover the couple mpg gears will net you. It will take years to recoup that difference.

Talking net expenditure, not worth it.

Spinning the 4x4 stuff isn't helping and neither are those aggressive tread pattern tires. You can whack a couple mpg off the ideal just because of those factors right there.

Now, if you want dual exhausts and a really "neato" air filter because you like it, go right ahead. Not going to do much for mpg though. You'll spend more on the parts than you will ever make back in mpg. You'll get more from just changing your route to work, a change in driving style or just not using drive through windows.

As to the throttle body spacer on a vortec, do a site search and see what you find....

 

[1998K1500]

Wasting your money if you're chasing mpg.

higher final ratio is where you want to spend your money for mpg in your particular truck.

However, if I were you, I wouldn't waste my cash on it.

The most you'll squeeze out of it on a good day is 15-16 mpg. That's with an engine and transmission in good shape (IE: not a 150-200,000+ mile vehicle), the rest of the vehicle in top shape, driven properly and in favorable weather/road conditions.

Changing the gearing will run you anywhere from 700-1000 bucks, maybe more. That buys a lot of gas to cover the couple mpg gears will net you. It will take years to recoup that difference.

Talking net expenditure, not worth it.

Spinning the 4x4 stuff isn't helping and neither are those aggressive tread pattern tires. You can whack a couple mpg off the ideal just because of those factors right there.

Now, if you want dual exhausts and a really "neato" air filter because you like it, go right ahead. Not going to do much for mpg though. You'll spend more on the parts than you will ever make back in mpg. You'll get more from just changing your route to work, a change in driving style or just not using drive through windows.

As to the throttle body spacer on a vortec, do a site search and see what you find....

This hit the nail on the head x2

Dual exhausts are cool, but don't do it expecting better MPG, you'll never notice it. And the only way you'll really see a marginal improvement in MPG is if you did headers back, which isn't cheap. It's worth it for the cool factor, but not for saving money.

 

[98_k1500]

Yea, TB spacer is useless on a vortec because of the style of injection on them. It makes absolutely 0 difference. Just judging by the gauge is not a accurate way to calculate mpg. If you went 10 more miles, it wouldn really show on the gauge, but would throw off your mpg figures by alot. Get us some accurate numbers and we may be able to help you a little more.

 

[77Impala]

And fuel level gauges are not always accurate. On both my GM vehicles they hover over the full mark for over 60 miles and then start dropping like a rock in water. On my Impala my wife will tell me it has half a tank of gas but it is more like a third of a tank left when I go and fill it back up.

 

[96k2500chevy]

Alright I appreciate it y'all. I'm getting a ultra gauge so I'm hoping that will give me a better mpg reading. And as for the parts I'm adding. It's just for looks and sounds but if it helps any mpg at all that's just a perk haha.

 

[98_k1500]

You need to fill it up, run it, fill it up again, and calculate actual mileage lol, burn a whole tank and see how many miles you go vs how many gallons you burned. Thats the only way you get an accurate reading.

 

[TylerZ281500]

your numbers and every thing everyone else has said is spot on, my two friends bone stock 95 and 98 both hit about 9-10mpg with 240 and 350k on them. both are in good running shape but nowhere near new, add oversized tires and such and thats just about where youll be. ive spent numerous hours of my life trying to squeeze performance and mpg in my truck, and it was more of a pain that it helped. i max at about 13.5-14mpg city on a good day and 18-19 hwy. i wouldnt be concerned that its out of the ordinary, and like everyones said fill up the truck and count your mileage next time you fill it back up.

 

[1998K1500]

I'll second the fuel gauges aren't accurate - I get what looks like great MPG through the first half, but then it drops suddenly.

You need to know how many gallons your tank holds - it's 25 if you have a short bed. If you have a long bed, it might be 34.

So fill up your tank and see how many gallons it filled. Then figure out how many gallons you really used then calculate based on how many miles you drove.