I have driven almost 30,000 miles already this year so whatever I do, I can't make this truck eat a lot more gas or throw MIL codes.
I'm taking in all the suggestions and considering several things.
I looked at a 6.1 with 84,000 miles. The man wanted $5500. That is REALLY steep compared to a $1500 5.7 with the same mileage.
I am leaning toward a low mile 5.7 and using a 6.1 cam with those shorty headers. To me, that should not adversely affect the mileage or throw any codes.
I can get 3.92 gears from a wreck for a good price or just swap over the whole axle. New gears will be digging into the wallet deeper than I'm ready to do. Maybe the 3.92 isn't much of an increase over the 3.55 but I know with a car I can feel the difference between a 3.55 and a 3.91.
Although not a huge seat of the pants difference, you will still feel the 3.92 gear, particularly on the low end. The effects on fuel mileage will be insignificant at the most. Probably speaking the obvious, but it is probably time to check on the u joints at the same time as a gear swap.
If you do go anything but a stock 5.7, you will need to get a programmer in order to shut the MDS (cylinder deactivation) function off in the PCM, Speaking the obvious, you will need the proper non MDS lifters to go with a 6.1 or any other cam.
Considering you will need the tune for the different cam setup, you may as well have someone such as Jay Greene or Hemifever Tuning write a custom tune to help free up some torque management and additional power.
Hell, even if you went with a stock 5.7 and remained with a 3.55 (add normal bolt ons such as cold air intake, headers, exhaust), a custom tune will make the truck feel much more lively than current.
Justin
