A Pickup Truck Project

[Big Dave]

High-MPG cars sell at a steep premium, new or used. Not everyone is as good a mechanic as Red or Johnny Mullet and willing to take on a well-priced junker.

Pickups are selling at a steep discount. You will get hosed when you sell it. This simple fact keeps a lot of gas hogs on the road.

A mod project is a do-able middle ground, attractive to a high-mile driver.


BGD:
Ford, Dodge, and GM have found that an automotive automatic is a marginal thing behind a pickup-sized diesel. I had an old 6.2 diesel in a GM. The engine was durable and efficient but that sucker ate seven automatics.

[Tony Raine]

sounds like a good idea. around my area, truck/suv prices are dropping like crazy. '06 f-150, reg cab, 2wd, v-8, automatic, low miles..... guess how much? $3,000.

there are still people that use trucks, that need trucks. buying a second rig (a gas sipper) is another payment, more insurance, and more regular maintenance/repair. those $500 beater cars that nobody wanted 5 years ago are selling for many times that now.

You will get hosed when you sell it. This simple fact keeps a lot of gas hogs on the road.

yup! ever look at the resale value of an explorer sport? its an SUV, so the car people don't want it. its a 2-door, so the soccer mom's don't want it.




if gas/deisel prices keep going up, i bet you will eventually find a deisel owner desperate enough to take on a project like this.

[dcb]

But an $8000 mod? There are a lot of reliable and decent mpgable vehicles out there between "well-priced junker" and $8000. It is VERY difficult to get cost effective mods on your vehicle if you are dependent on someone else to do the work. I will continue to encourage folks to learn this stuff for themselves. You *could* do a boneyard manual trans swap AND rearend and cut your springs on many trucks for $500! And have it payed off in a month!

[Tony Raine]

Originally Posted by dcb

But an $8000 mod? There are a lot of reliable and decent mpgable vehicles out there between "well-priced junker" and $8000. It is VERY difficult to get cost effective mods on your vehicle if you are dependent on someone else to do the work. I will continue to encourage folks to learn this stuff for themselves. You *could* do a boneyard manual trans swap AND rearend and cut your springs on many trucks for $500! And have it payed off in a month!

your ideas don't really apply to the planned vehicle. swapping transmissions, even if "easily" doable, will open a can of worms on a 4x4. transmission mounts, any transfercase mounts, and BOTH driveshaft lengths. and cutting -springs defeats the purpose a deisel, crewcab, longbed.

btw, you just don't run the overdrive unit when in 4x4. the key i think is installing the overdrive unit yourself. can't be that hard. then drive to driveshaft shop in front wheel drive, get your rear shaft shortened appropriately (about $100 tops), and bolt it back in.




i really see the price being half this estimate.

-truck - already own (whoever the future guinea pig may be)
-trans mods - if you have owned the truck awhile, chances are it needs trans work already, so i feel this applies to preventative maintenance.
-overdrive unit - just buy it, and install yourself
-tools - socket set and a floor jack? (any DIY'er should already have. you could replace the floor jack with extra pushups)
-Soft flat tonneau - go cheap. vinyl on a roll, snaps, and a sewing machine
-Stock wheels with Mooneye covers - once again, go cheap. you have a truck, you can pick up all kinds of "material" right off the side of the road.


and you still have a truck that does what you bought it for. and you dont have to worry if the little car that big al's used car dealer sold you for way too much money, will leave you sitting on the side of the road at a most in-opportune time.



of course, all this means nothing if someone just bought the truck to look cool. or if they drive a lot of highway miles without a load. thats when they need to buy the econo car.

[TEiN]

Hey Big Dave,

I'm driving a truck similar to what you're looking for: 2006 F350 4x4, Long Bed, Crew Cab, Automatic Transmission, single rear wheel, w/ 4.10 rear end. Except for running 80psi in the tires, it's all stock with 36k miles. With stock air pressures in the tires, and "normal" driving habits, I was getting <12mpg city, and 13.8mpg hiway. I aired up the tires to 80psi (sidewall max), installed a ScanGaugeII, and started paying attention. I do some coasting in neutral with the engine running, some DFCO. I now easily get >17mpg city, and >23mpg hwy.

My FE would be a lot better but I drive a LOT of short trips, and a lot of the time the engine is cold. My truck gets 20-50% worse FE when the engine is cold. Also, my house is at the top of a pretty good hill with a 0.4mile long steep gravel driveway. Going up that driveway a few times a day at 5mph really kills the mileage. And climbing the hill at the bottom of the driveway when the engine is cold kills it too...

Today I had a best-ever day, with a 34.6 miles country-road round trip that averaged 27.2mpg. I had to re-run the same trip later in the day, and got 26.4mpg (I drove faster on outbound leg of the second trip because I was late). Average speed was 42 mph the first time, 43 mph the second time. Slowest speed was stopped =), lowest speed limit was 30mph, highest was 55mph, 90% of the route was 45mph speed limit.

No aero, no mods (except for tire pressure and ScanGaugeII)... 27mpg in a 8,000 lb. 4x4 truck. I think your 20mpg estimate is low, and your $8k estimate is high.

Also, trucks with the 7.3 liter engine like yours seem to get better mileage with load than the newer 6.0 or 6.4 liter engines do. Towing my 10,400 lb. trailer (very tall and square) in the very hilly terrain in Oregon gets me ~9mpg. I don't know that running a big overdrive gear would get the same good results that you're getting with yours. On mine the FE plummets when the LOD gets above 50% (on the ScanGauge).

[Big Dave]

No doubt about it, the old 7.3 school bus motor is the most efficient of the PowerStrokes. The 6.0 has EGR. The 6.4 has EGR and DPF. Both those items rob efficency and the 444E has neither.

Once again it is proven that the best mod is done to the nut behind the wheel.

[max_frontal_area]

so this project turned out to be a lead zepplin? bummer.
my one additional suggestion on an older truck would have been to grill block,
and go with electic fan. under cruise in an empty truck you don't need to send lots of air through the engine. now on a modern super duty i counted
EIGHT heatexchangers, you block a lil to much on a rig like that and you will pay!

who, OEM or aftermarket makes the most efficient 4.10 single wheel rear end?
reason for asking the ford 9'' is very popular with rodders because of strenght and efficiency - perhaps there is a difference in trucks as well?

[MechEngVT]

The Ford 9" rear is one of the least efficient of the common mass-market rear axles. It is a semi-hypoid, where the pinion gear is further offset below the axle centerline than a pinion would be in a typical helical bevel gearset. Hypoid gears are at least 3% less efficient. The Ford 9" rear is popular among hot rodders because it is common (i.e. inexpensive and its ubiquity provides many gear ratios to choose from), it is a "quick-change" style rear (the ring/pinion/carrier is assembled to the pinion housing as a unit which drops into the axle housing), and the low pinion allows driveshafts to clear in low-slung street rods and lowriders. Efficiency has nothing to do with its popularity.

A GM 10 bolt or even a 12 bolt would let you recover that 3% efficiency loss from the gearset alone. It would be a pretty big deal when you're talking about gearsets that are about 94 vs. 97% efficient.

[brucey]

I don't know. Big dave has done a lot of the stuff he was talking about here. He got the overdrive, the air dam, the aero cover on the back. Take a look at his truck. He is averaging nearly what my car averages in an F350. Not too shabby?

[max_frontal_area]

Originally Posted by MechEngVT

The Ford 9" rear is one of the least efficient of the common mass-market rear axles. It is a semi-hypoid, where the pinion gear is further offset below the axle centerline than a pinion would be in a typical helical bevel gearset. Hypoid gears are at least 3% less efficient. The Ford 9" rear is popular among hot rodders because it is common (i.e. inexpensive and its ubiquity provides many gear ratios to choose from), it is a "quick-change" style rear (the ring/pinion/carrier is assembled to the pinion housing as a unit which drops into the axle housing), and the low pinion allows driveshafts to clear in low-slung street rods and lowriders. Efficiency has nothing to do with its popularity.

A GM 10 bolt or even a 12 bolt would let you recover that 3% efficiency loss from the gearset alone. It would be a pretty big deal when you're talking about gearsets that are about 94 vs. 97% efficient.

thank you for the clarification on the 9" ford. miseducation @ work, many places i read more efficient, stronger, better...

now for the 4:10 "i was headed the other direction" what i need is a 3.31 or a 3.55. i need to lower engine rpm desperately. the truck is an 86' f-250 1/2 ton/single wheel, xt cab.
since you are recomending GM, will the axle fit? bolting up to the springs seems universal but how about shock mounts and brake connections.
also is the displacement from the master cylinder appropriate for the drums
of the GM axle? am i likely to find this axle at the wrecking yard?
if i find one with disk brakes would it be preferable?
finally, how many teeth would i be looking for on a 3.31?
ty!!