stepside vs fleetside mpg???

[Billybob13]

hey yall well i havea 83 lwb fleetside as a daily driver right now but her 13 mpg is killin me and ive heard that stepsides get better mpg so i was hoping someone could help me out on this because after my blazer project i might convert her to a lwb stepside if it will help at all and any other mpg tips helpits a 305 motor 700r4 trans thanks

[old Rusty C10]

I dont see how there would be much of a difference if any but ive been mistaken before

[chevymotocross]

x2 what old Rusty C10 said.

305/700r4 is a good base for decent economy. What gear ratio? What size tires? Is that 13 city, mainly highway, or mix? You driving easy or aggressive? Has it had a tune up recently?

If the 305 is in good healthy condition and you have a good gear ratio and drive it easy, you should see atleast 15. My 87 with the 305/700r4 and 3.08's gets 18 mix but it is TBI.

[Billybob13]

31 inch tires she could use a tune up dont know why i didnt think bout that she is good motor carb is a lil on iffy side thats a mix number and mostly easy but i show her off sometimes and no idea about gear ratio

[chevymotocross]

31'' tires are definitely bigger than stock c10 tires. Your mileage readings may be off due to that. Also, 31'' is a big tire for the common 2.73 - 3.08 found in most c10 trucks. If it has a 3.42 or lower ratio, like a 3.73, then that shouldn't be too bad. The glove box numbers should point you to the ratio with a decoder, if the sticker is still there.

[Billybob13]

whatelse could i do to check ratio the oldman i got truck from peeled off sticker

[TwoFiftyShifter]

If anything, the stepside will get worse mpg at highway speeds, since the exposed fenders would create more aerodynamic drag.

You really need to figure out your gear ratio. If you had a working tach and gps you could give us your reasings and we would figure it out, but what you would do is jack up the back of the truck, then you mark the tire in one place, slowly spin it one revolution. At the same time you need to watch the driveshaft and count how many turns. If it turns 3.5 times, probably 3.42, if it turns 3 times, most likely 3.08 and so on.

[lilpoindexter]

My 78 250/ 3spd manual stepside gets 12mpg in mixed driving. These aren't the vehicles for you if mpg is a concern.

[Gadoozle]

Originally Posted by lilpoindexter

My 78 250/ 3spd manual stepside gets 12mpg in mixed driving. These aren't the vehicles for you if mpg is a concern.

I agree, if your concern is fuel economy, maybe you should get a car that does not have a V8.

[Billybob13]

i cant get rid of em love tomuch and im 6foot 303 lbs so cars aintmy friend haha i just wanted to see if i cant raise any cuz no matter what its my dailydriver

[lindstromjd]

Easiest way to get better fuel mileage from a v-8 is get a diesel.

[spudz]

stock 5.3 and 4l60e. should put u in the 20s.

[lindstromjd]

Originally Posted by spudz

stock 5.3 and 4l60e. should put u in the 20s.

Boo for computers. :P

[Billybob13]

a older detroit diesel conversion is always an option right? or are they perty bad on gas themselves

[pooods]

Don't think you would notice much if any of a difference but like mentioned above the turbulence from the fenders would cause a slight loss of MPG.
Kinda reminds me of the old trucking companies that owned box trailers with ribs on the sides. After purchasing a fleet of new trailers with slick sides and seeing the difference in MPG along with noticing how much easier they were to pull they sold all the old ones and upgraded to all slick sides. Catching less wind and being as straight as possible is a good thing.

[goatwrangler]

Originally Posted by Billybob13

a older detroit diesel conversion is always an option right? or are they perty bad on gas themselves

they arent bad on gas at all...they wont run on it either lol. sorry i couldnt help it. the 6.2 i think should be around 17-18mpg highway maybe city too ? just depends on how heavy your right foot is. (or left if you're missing your right)

[Billybob13]

so ditch stepsideidea and the detroit conversion seems like to much for 5mpg havin to do motor, trans, axle, etc. but hell itd give me somthin to do also it has rochester q-jet if i put a small edelbrok 4bbl would that help seein as how massive the rear jets are and two fifty i have a tach installed on her and i have my bros gps so yah

[BigRed76]

My '76 shortbed used to be a stepside, and when i swapped in a fleetside I lost 2 mpg instantly. I was able to remove the stepside bed by myself because it was so light, and the fleetside bed is much heavier.

[Billybob13]

well still nun to major of increase

[lindstromjd]

Originally Posted by Billybob13

a older detroit diesel conversion is always an option right? or are they perty bad on gas themselves

My 6.2 Detroit is AWESOME on fuel mileage. I get about 18-20 mpg's in town and 15-19 on highway. I have 3.40 gears and a turbo 350 trans, and a reeeeaaaaaally light foot. Explains the backwards numbers. That, and that stupid 3 speed kills my mileage at 75 mph. I need an over-drive. And a turbo.

I don't think you're going to get better fuel mileage out of an aftermarket carb. Q-jets are made to be extremely fuel efficient, as long as you stay out of the secondary barrels.

The diesel conversion is actually really simple, and very straight forward. It bolts right up to whatever transmission you have, and only requires a different, "diesel-style" torque converter to make it work. The power curve on them is almost identical to a SBC, too, so you're not going to be at any loss if you do want to do a swap. I just swapped a 6.2 into my truck to replace the 350. I love it.

[355bullet]

i own both 1986 stepside and fleet. Both are pigs with fuel. Both run 373's with 33 inch tire. No way around it, they both weigh over 4,000 lbs. my 1970 gets better fuel mileage and weights 31 or 3200
For better fuel economy up date to the new engines. Thats what im looking into already. This forum of shared know hows have made it simple.
That too, thanks for the shared info!!

[S10Fan]

My 454/700R/670 Holley equipped Stepper gets 16-16.5 with the cruise on at highway speeds. The truck does around 13 in town using 3rd gear.

When it comes to fuel economy your right foot can be friend or foe. I love driving my truck, driving sensibly and following the speed limit gets me a few more minutes behind the wheel.

But, if gas mileage is the main concern, go hug a tree and by a Prius.

[GmtGmt]

Originally Posted by Billybob13

she could use a tune up

before you start on anything do a tune up first i see alot of people complaining about there veichel is getting bad millage but mostly its because they dont maintain them proberly

change all the oils Motor, Trans, and differential, plugs, wires, cab and rotor
and use some high quality stuff not some cheap brand
you wont belive that its the same truck

[red rumbler]

your going in the right direction with a 4 speed auto but you gotta figure out your gears bigger the number the worse your fuel economy. if your gears havent been touched you'll probley have 3.08 or maybe even 2.73s like chevy motocross said. and if you dont wanna go that route you could always take the tranny to a tranny shop and have them lower the gear ratios. you wont be lifting the front wheels of the ground but itll improve it. also lighter is always better. if youve got junk in the back for no reason toss it every pound counts. and if you wanna take that to dramatics there is a company that makes a full front clip including hood for 2200 and it only weighs 45 pounds or so compared to our steel fenders and hood.

[justinburnett]

I get 10mpg on the highway if it's flat with no wind. I'd be loving 12-14! Granted, i've got a 3/4 ton 4x4 with 4.10 gears or so and a th400. No wonder, right? My other car's an old datsun 210 and gets 35-40mpg so I make up for it there when I commute.