Best money spent for better mileage on an 03 6 spd?

[glhs]

My brother has purchased a 2003 6 spd w/3. 73s.

What can he do to improve mileage? Specifically, which chip, tires, gears, exhaust, intake?

Would his truck have the G56 or the NV5600?

I'm just not familiar enough with 3rd gens to steer him in the right direction.

Thanks,

Kurt

 

[wcjp]

G56 wasn't available until 05. 5'. He has the NV5600. Cheapest solution for mileage is slow down. Leave the tailgate up.

 

[moonranch]

The biggest single improvement I got was from the Smarty Jr. (set on max hp/#3) The biggest loss I got was changing from the stock Michelins(265/70R17) to 285/70R17 ProComp ATs. I have made quite a few mods, and have gained about 3. 5MPG overall.

 

[Joseph Donnelly]

Either the TST PowerMax-CR or the Smarty will add timing and I have found 1-2 mpg from either of them. I believe Edge is also making a box to add timing. Stage 1 injectors like DDP will help 1-2 mpg, as will fresh injector bodies if there are a lot of miles on the truck (say, over 100,000). Beyond those modifications are the “obvious” things—use stock size tires and no lift kit for minimal wind resistance, don't carry more weight than necessary, optimize driving habits, and lower your rate of acceleration and your road speed (say, 65-72 mph rather than 75-up). The six-speed transmission will be the New Venture 5600 with iron case.

 

[glhs]

I see the new '09s can be had with 3. 42s; is a change to this ratio available?

Any improvements from intake manifold horns?

 

[Cattletrkr]

Dad bought his '03 used with and it came witha Banks 6 gun. Mileage was nothing to brag about so we pulled that in favor of an EZ. Mileage went down towing and about the same empty. He left it in because he like it better. Since I sold my '04 we've been toying with my Smarty in his truck. Setting 3 seems to be giving the best mileage. About 2mpg better I think. He used to have a hard time staying over 16mpg on a nice easy lazy long drive. Now he's running anywhere from 17-19mpg.