Well here are the details of my trip.

had 12 gallons in the tank, drove about 50 miles up the mountain and about 5 miles into a trail. Had to pop it in 4 low for about 5 min. Then coasted down the mountain going no more than 65, so about 110 mile trip.

Load: 4 people(about 680lbs) gear: about 130lbs

I went no more than 50 miles an hour the whole way and there are no stops. I was casting through the corners and would ease into the thorttle not jack rabbit around corners.

My tank is at the red mark and I am almost out of gas. I forgot to mention that my gas mileage is maybe a little better at most in town. Whats the deal?

-tire pressure is at max stick psi
-i dont have lead foot syndrome
-no check engine lights
-i get about 9-10 mpg
-recently changed the spark plugs(the other ones were fine and i was still getting bad gas mileage)
-i do have a CAI but it has a oversized air filter on it(problem?)
-173k on orig engine(i think)
-might have rebuilt tranny, not sure. It doesn't slip at all but there are some noticeable losses of power driving up the mountain(torque converter?)

problems:
-needs new rotors
-small header leak

I am stumped at what to do to improve the mpg, I cant afford it for much longer.

Any input would be great! thanks!

 

First thing I have to mind, is what gears are you on? My city MPG went to crap as well when I put my 31's on, because I still have the tall 3.55 gears. Yea, it makes my highway milage flirt with the 20's, but i'm only getting 12-14 mpg city. That would also explain your loss of power going up hill, which is probably what drank your MPG, especially with nearly a 600ish pound extra load than normal. Also, did it downshift at all going uphill? OD would load the engine worse uphill, if it didn't downshift to 3rd..

 

[quote=SpencerS;2274036]

-i dont have lead foot syndrome
/quote]

i do!, but you did have a lot of extra weight and going up a mountain. i know my truck eats through gas when im in 4x4.

 

i have 3.55s yea! it would stay in third all the way up the mountain at about 45 mph. Then when i would almost be flooring it, it would shift into second. This is with OD off!

It just really hurts the wallet i dont think i can make it even to the nearest gas station lol. Im not really complaining because i love my truck but man you gotta take a spear to the side to keep it around lol.

 

i dont think this is a gearing problem i have the NV3500 so I know its stick but its geared a little lower...maybe only 1st and 2nd I forget but my rear is 3.92 and I get 20-22 almost every 150 mile trip to or from school and that is highway 60-65 mph highway 65-75 mph and a little stop and go as well...it could be that the trans wasn't rebuilt right or maybe you have some time of braking issue with one grabbing and you don't know it but it really should be that bad have you taken it to a good respectable mechanic?

 

But that's highway. I'm going to 4.10's in the very near future. Right now my effective gear ratio is a 3.20 something. My truck struggles to pull our empty car hauler, that's around 2000-2500 pounds. It stays in second gear until about 45 MPH, or if I let off. But I'm only a V6.

With no payload, I can be going up even a smallish hill with cruise turned on, and it'll go from OD to drive, then drive to second. BTW, it's quite scary to be going 60 MPH in second gear. It freaked me out the first time, but I'm used to it now...scares the crap out of my dad if he's with me. I've actually had it try to go to 1st gear a few times, and banged the rev-limiter pretty hard (and put the trans in neutral of course).

Like i said, i'm only getting 12-14 MPG city, I'm hoping going to 4.10's will get my speedo back closer to accurate, and gain me some city back.

 

i agree but I also haven't seen worse than 15-16 with the truck in 50k miles and he has the same motor just an auto instead of stick so thats what i'm basing it off of and that was beating it with basically 1-3 gear and maybe 10-15% 4th on the back roads around me...im not disagreeing at all that you'll probably get better mpg especially city with 4.10's with a V6 just saying he should be getting better than 9-10 so something is def wrong

 

Its hard to find good respectable mechanics around my town because there are alot of them. Im still looking! But I will probably take it in once i sell my MX bike!
Ive got about 2 grand to work with so we will see if i can get a shop to pull off a 5 speed swap.
Id kill for 20-22 mpg on the highway!
Do you think the bigger air intake could cause it to run to lean(Air:fuel) and worsen mpg?

 

I get around 230 on a tank of gas in my truck. 5.2 auto,4x4 new plugs cap rotor and wires bumped it up 3mpg Im now getting about 13mpg depending how hard I drive which normally it doesnt matter to my truck if I take it easy or beat on it seems to get the same mpg. I would check your cap,rotor and wires if you havent changed them it wont hurt. My truck is just weird I had 1,500 lb on my truck seemed to get the same mileage as when we had 3,400lb on.

 

i don't think the intake alone would make it run lean. maybe with a bigger tb and headers. the filter size shouldn't matter, the bigger ones look cool but imo it flows the same cause the inlet is the same.

i know 4x4 kills my millage, last winter i got as bad as 11 mpg. so with more truck then me i think your fine, maybe get some skinnier friends lol.