Pretty much bone stock drivetrain. Very tall rear end gears (2.73:1) probably the biggest contributor to the mpgs. Gradually replacing parts and improving the performance, which will likely sink the mpgs in the long run.
Currently down for engine swap (Vortec 350), transmission rebuild/upgrade, and shorter rearend gears (3.73:1 perhaps). In process of rebuilding trans., have new engine ready. Been delayed like everything, hope to finish for next summer.