Fuel Economy

[Giant]

I didn't think anything of it when my 99 Yukon 5.7L V8 with 94k miles was only getting like 14-15 hwy and like 11-13 in town milage. After talking to my dad he feels it should be getting closer to 20 hwy.

 

It idles smooth as if it were brand new so I didn't think the throttle body could be dirty.

 

This is what I found when i dug into it.

 

 

Also would I need new plugs? Here is a picture of those

 

 

 

The air filter can also probalby use a change. the other thing I was going to check was the fuel filter. Where is the fuel filter located on this beast? The other thing I guess I could get new plug wires too, but if all this stuff was wrong with it, I don't think it would idle as smooth as it does.

 

to see some other pics of the engine go to

 

my Photobucket page

 

Thanks

-Robert-

[Truckman031]

You won't get much better than that. That's about what my 98 Z71 gets. The 350 likes to drink gas. If you had a 2000 with the 5.3 then you might be able to get some better mileage.

[Giant]

Thats what I'm affraid of. I'm headed back to my parents house for x-mas. It's 1000 mi one way and with gas prices I was looking to squeeze every last mpg I can out of her.

[redvett]

If i remember correctly my 96 350 4x4 with 3:73 EXT pickup had a HWY of 16 mpg on thewindow sticker and it seems like i got about 12 mpg city. Sounds like your right on the mony with fuel economy.

[95Sierra2500]

If you'd like to increase your mileage, you may have a few options but not many that are going to be cheap. Here's a few things you can do:

1. bump up your tire pressure to the max. This reduces the rolling resistance of your tires and can give you anywhere from .2 to 2 mpg.

2. invest in a topper or tonneau cover. This will help reduce drag and can give you a half to a full mpg.

3. it might be time for a tune-up, as this can sometimes help to improve mileage. However, it sounds like your truck isn't doing too bad, so you might be able to skip this.

4. try running synthetic oils in your engine, trans, and differentials. synthetic fluid reduce friction and can give you anywhere from 0-25% increase in mpg.

5. Slow down to the speed limit and set the cruise. You will use less fuel by not speeding, and the computer does a MUCH better job keeping your speed steady than your foot ever can.

[chakis24]

5. Slow down to the speed limit and set the cruise. You will use less fuel by not speeding, and the computer does a MUCH better job keeping your speed steady than your foot ever can.

 

<{POST_SNAPBACK}>

 

 

 

that only works on level ground though. when i drive from school to home i did it with cruise most of the way, and i was getting in the low 16's, but then when i was pushing the pedal myself, i got in high 18's. when you go up a hill the cruise like to make the engine hit 3500 rpms easy, meanwhile when i drive it, i never go more than 2500. all that revving and backing off in the mountains doesnt help mileage.

[Giant]

Do I have to take the TB completely off to clean it? Will the solvent hurt anything by dripping into the intake? I know a litle won't hurt anything, but with the TB horizontal, all the solvent will drip inside.

 

Thanks

-Robert-

[95Sierra2500]

5. Slow down to the speed limit and set the cruise. You will use less fuel by not speeding, and the computer does a MUCH better job keeping your speed steady than your foot ever can.

 

<{POST_SNAPBACK}>

 

 

 

that only works on level ground though. when i drive from school to home i did it with cruise most of the way, and i was getting in the low 16's, but then when i was pushing the pedal myself, i got in high 18's. when you go up a hill the cruise like to make the engine hit 3500 rpms easy, meanwhile when i drive it, i never go more than 2500. all that revving and backing off in the mountains doesnt help mileage.

 

<{POST_SNAPBACK}>

 

 

 

 

You bastards and your special situations. Okay, so for mostly flat ground and small hills (what most of the country is, anyway) setting the cruise is the best thing to do. Oh, and if you're making enough power, your truck isn't gonna downshift as much.

[Giant]

Yeah, the trip home will be mostly flat. From VA to WI other then a couple hundred mi's through the moutains in PA, its pretty flat through IN,OH,IL etc...