'01 GMC Sierra 1500 is worthless

[pgfpro]

Originally Posted by darcane

The number on thing I've done is removing the ladder rack that was on it when I bought it.

Is yours 2wd or 4wd? My best so far is a little over 19mpg. Mine is a 2wd and stock except the canopy and I've upped it to 45psi in the tires.

-Mike

Its a 4wd.

[pgfpro]

Originally Posted by Backtobasics

I question the need for premium?
Higher octane rating actually burns slower then lower octane. HP applications need the octane higher to resist pre-ignition. I doubt your truck actually needs it.

Electric fan?

I know it was a stab in the dark.lol But the dang thing pings all the time when I'm on the on ramp so I decied what the heck i'll try a higher grade fuel.

[Big Dave]

I feel your pain. My Impala is the same way.

Your options:

1. Don't drive it too much (under 7,000 miles/yr) and don't worry about it. If it has no monthly payments, that covers a lot of sins.

2. If you drive enough to motivate change, consiider trading it in, take you trade-in beating and buy a high MPG-car. Since you already have a high MPG car and still need to drive the truck I presume you have a need for it.

3. Become a hard-core, fangs-out, foaming at the mouth ecomodder.
What is killing you are:
a. The gas engine
b. The automatic transmission
c. The numerically high gear ratio
d. Lousy aerodynamics

Solutions:
A. Chuck the gas-pig motor and swap in a Cummins 4BT3.9 diesel
B. Chuck the frail, expensive automatic and swap in a T-56
The tranny swap kills two birds with one stone. You make a huge mechanical efficiency gain and the T-56 has a huge 0.5:1 overdrive which cures the problem with the gear ratio.
C. Chuck the flush top canopy and bribe Bondo to make you one of his superb Aero-Lids.

Do all that and you are in the high 20s to low 30s.

Low RR tires will help. Goodrich Long Trails are good in your size range.

Pidddle-around efforts yield piddle-around results.

[Big Dave]

Premium gas theoretically should help this truck. GM PCMs listen for knock and automatically retard the ignition til the knock goes away. If you run 94 octane gas the engine will run max advance, theoretically improving engine efficiency, hence MPG.

Doesn't help my Impala a bit.

Everyone wants to live in theory because everything works perfectly there.

[bgd73]

Originally Posted by pgfpro

I needed a break from my Honda so I started trying to up the FE in my GMC Sierra 1500.

This thing is a fuel hungry monster. I have tried all the easy mods and have had no luck

I can drive this thing like a "Bat out of Hell" or like a grandma going to church and it gets the exact same mileage.

Anyone have any suggestions for this beast???

all of injected gm v8 is frustration. you may find 14 mpg is their own cap. my next plan for my brothers rather rare extreme duty (a real hauler) 3/4ton with 11:1 compression was dismantling the top end, removing the cam, going for an older setup of carburator and proper cam and untake using the depth high compression can. There is no other way out...the gas will double BTW going old school, dropping fuel pressure, 3 degree timing, very taught and disciplined. the exhaust is lean and need attention afterwards. the heavy duty trucks had extra coolers already. the gm v8 reveals all fuel injection of all machinery...it is a dead end.
If it were not for my first truck, called a haevy half ton in the 20s mpg on the highway and so very calm at an idle with a large freakin engine, carbed, old school, and only a 3 speed auto...I would never have guessed it, going back in time is the answer. today you get one more gear in the autos, and a 5 speed. there is a real oppurtinuty if to step back from the morons injected railroad.

[RobertSmalls]

Driving technique should make a big difference. If it doesn't, you're doing it wrong. Maybe quick vs slow acceleration doesn't make much of a difference with your powertrain, but I guarantee that truck uses more fuel at 65mph than at 55mph, and you'll use less gas if you drive without brakes.

[2000mc]

looking at how many more miles per gallon you get trying to hypermile a truck can be discouraging. hopefully youre looking at the percentage change. getting 1 more mpg in the truck would be similar to getting 4 more mpg in your del sol.

but yea, i cant move my trucks numbers around alot either. '91 k1500 5.7 normally runs 13-13.5mpg. i can pull a car trailer w/car and only drop down to 11mpg. i've taken a long trip to pick up a motorcycle for a friend, set the cruise at 60 and proceeded in burning off a full tank full in one straight shot and only managed 17.07mpg. so best case scenario i only get like 3.5mpg better...but thinking percentage wise, if it was you del sol, that amount of change would be similar to like 15mpg difference.

[Christ]

Try unplugging the knock sensor for a trip, see if you can get it to drive normally without pinging without the ECM getting involved.

[pgfpro]

Originally Posted by 2000mc

looking at how many more miles per gallon you get trying to hypermile a truck can be discouraging. hopefully youre looking at the percentage change. getting 1 more mpg in the truck would be similar to getting 4 more mpg in your del sol.

but yea, i cant move my trucks numbers around alot either. '91 k1500 5.7 normally runs 13-13.5mpg. i can pull a car trailer w/car and only drop down to 11mpg. i've taken a long trip to pick up a motorcycle for a friend, set the cruise at 60 and proceeded in burning off a full tank full in one straight shot and only managed 17.07mpg. so best case scenario i only get like 3.5mpg better...but thinking percentage wise, if it was you del sol, that amount of change would be similar to like 15mpg difference.

I hear what your saying. I'm just hoping for a 1 mpg increase on my personal best. But I think its not going to happen.

[pgfpro]

Originally Posted by Christ

Try unplugging the knock sensor for a trip, see if you can get it to drive normally without pinging without the ECM getting involved.

I'll give that a try. Good thinking!!!