mileage and durability build?

[westonoto]

I have a chance to pick up a good 3.0 engine (same as in my 99truck) for the cost of having the dead (rollover) vehicle towed away. I'm considering doing a rebuild on it with the idea of dropping it in my existing truck. For what I use it for, stock power levels are fine for me, but I'd love to get a little better mileage since I often have to make 500 mile round trips on the highway. Since I also spend a lot of time a great distance out in the woods, I also want it to have absolute reliability.

Any suggestions for specific areas of a rebuild to concentrate on? It may not seem like a big deal, but even a 2mpg gain would be great since I put about 40k per year on the vehicle at the current time.

Thanks

 

[Ranger44]

Check out Mustang Roller rockers, Mutant pony has them on his 3.0. He says they improve acceleration, reduce noise at high rpm's, smoother operation, etc. Whenever I get my 3.0, this will be an option I'll look into.

 

[Wicked_Sludge]

properly maintained, a 3.0 can go 300,000+ miles without opening it and get 26+ MPG in certain trucks...i dont see what more you could possibly want

i know what your asking...but i just dont think there is much room for improvement.

 

[westonoto]

Yeah, durability wise, it's probably fine as is. I have 180k hard miles on mine with no failures and nothing more than common sense maintenance. Mileage wise, though, I'm one of the 15-18mpg club at best. Been that way since new. I have a 20 year old beater/plow truck 350 chevy that gets better mileage.

I've tested and/or replaced sensors, components, electricals, injectors, etc trying to get better mileage, but no luck at all. I even had the chance to swap out a tranny/TCS from an identical truck (except his got 23mpg highway) and it did no good.

So far, the game plan on the motor I'm picking up is to clean up air and fuel paths, rebuild the heads, rings (at least, depending on what things look like inside), bearings, gaskets, blah blah blah. I guess I was hoping someone might know a fuel efficiency weakspot in these motors since people either get the mileage of a big block like me, or have really good mileage.

Thanks folks

 

[Wicked_Sludge]

perhaps the mileage is less a function of your motor.

what is your tire size and axle gear ratio? what RPM do you shift at (when driving slow and when driving fast)? do you haul any extra gear? have you tried driving per a vacuum guage?

some things i was thinking about: spend some extra time polishing up your combustion chambers, the 3.0 likes to build carbon which causes so many pingijg problems...a good polishing will prevent this. our plenums, lower intakes, and heads were popped out of the molds and onto the motors...theres lots of potential for knocking off casting lines and whatnot. gasket matching will improve power. roller rockers will decrease wear (ever so slightly).