new guy with a silverado
 

Hello actually just found this site while searching for aero mods and tons of great info here. Anyways i own a 02 silverado ex cab short bed 2wd with the 4.8 and 4L60E trans. Recently moved and now my daily trip to school has gone to 65 miles round trip so obv i am looking to improve its mpg's, plus i love tinkering with different things. My goal is to improve mpg's while keeping the truck rather mundane looking. Some of the aero caps and other diy mods i have seen are great and i applaude you guys for taking that step but there just not for me.

Some things on my to do list:

Tonneau cover for the bed- seems most effective for price/looks/durability.
Belly pan- starting with front and space between frame and body and go from there.
Rear aero- gonna need some help in this department
engine related- electric fan swap and ecm tuning

Welcome as far as mods to keep your truck looking normal would be
-tonneau cover although i recommend you fab up an aerocap a lot more gains there
-electric fan swap could provide quite a bit beings you drive 65 mile round trip im guessing highway or close to it so it wouldn't come on a lot
-Air dam these tends to look oem and can be made for cheap.

I wouldn't be surprised if someone doesn't post this so i'm just gunna say it now buying another vehicle and keeping this as more of a toy. My brother had a 5.0 f150 and was getting about 15mpg driving about 30mi round trips everyday he went and bought a ford zx2 and the car paid for itself and insurance in fuel savings within 2 years. Some people choose to go this route others don't its up to you. BTW the zx2 is now my toy and is still running great.

There's basically 2 ways to get decent mileage out of a truck :
Drive slower and hypermile the heck out of it (as Diesel_Dave is doing), or greatly modify it (what BamZipPow and Aerohead are doing).

Miracles don't happen, I'm afraid ...

If modding isn't for you, slowing down and hypermiling like heck will be your part.


The alternative : ask yourself wether you really need a 4.8L truck and burn off your $$$ ...

I figured this would come up so... Do i really need a truck, well yes but only part time. I need it in the summer to haul my race car back and forth to the track. Unfortunatley i am a full time student and on a limited budget so keeping the truck and purchasing another car just isnt going to happen.

im in your boat, kinda. my fiance and i both work 30-40 hours a week at dead end jobs and go to school full time. we both drive about 1100 miles a month. i spend around $150 a month and to buy a car ($10,000) that gets 75mpg i would still lose money over keeping what i have. the ROI would be better for you because i assume you are getting at best 18-19mpg.

@300mi/wk and 15mpg you'd save $200 a month if you went to 45 mpg (easy in most FE cars)

How does your current fan run? IMO, a clutched mechanical fan is superior to an electric one. The clutch allows the fan to only be on when it needs to be, and it's more efficient than converting the mechanical energy to electrical energy and then back to mechanical again.

the general consensus is that the electric is more efficient... do you have facts to backup your opinion?

Thats pretty much what i figured too. So the money i would save goes away in car payment and insurance. thats keeping the truck.

although if i get rid of the truck i would be farther ahead, just in vehicle price paid 1k for the truck and could get 3k out of it.

dave heres my opinion on fans. The clutch fan (what my truck has), spins constantley even though the clutch is not engaged. My thought is just as any racer remove rotating weight from the engine to free up hp and tq. obv this helps with fuel economy when approaching grades. What i do know for fact is that switching to a electric fan and a simple 87 octane tune is a solid +2mpg on my platform, given the same application of the right foot.

Many hear bad results from electric fans because most think the bigger the better. Thats when someone ends up putting a giant pair of 3500 cfm fans on their vehicle pulling around 25-35 amps. A small electric fan and more importantly a PROPER fan shroud go a long way.

That being said i see your driving a 6-speed cummins, i would never consider taking the fan clutch of of mine. The drag from the fan is very minimal considering the very high tq low in the rpms.

Your truck is very similar to mine ('03 4.8L, 2WD ext cab long bed with canopy). Check out my thread in my signature. I built a belly pan, got an ultragauge (highly recommended) and adjusted my driving style, changed wheels, made a grill block and my commuting mileage went from 15mpg to about 20mpg.

I was going to do a Blackbear efficiency tune, e-fan, and cover the gaps outside the framerails under the cab/bed. In the end, it still cost too much to drive and now I have a Civic.

The front sheetmetal of your truck is the same as the 00-06 Tahoe. Look into getting the air dam from a 00-06 (not sure exactly what years had them) Tahoe for a clean, factory look that is effective. My wife's '05 2WD Tahoe with a 4.8L will average 25mpg highway whereas my truck will only do about 21. Part of that is the air dam, part of it is the electric fan, part of it is gearing, and probably some aero. E-fan on these trucks consistently show small mpg improvements.

Good luck, but don't expect miracles. It's still going to be expensive to drive.