@Princess Valiant (Or anyone else wondering about a OD trans swap and the effect it has on the final drive ratio for mileage.)
In order for the OD trans to work best to equal or better the mileage your getting with the current 2.76 gears, the below calcs were done to show the needed gear ratio to better mileage.
4.01’s & 3.91’s are out since they are numerically higher than your current gears. Current ratio - 2.76
2.76 X 1-1 = 2.76 (of course)
3.91 X .69 = 2.967 (2.97)
3.73 X .69 = 2.57 (Winner)
3.55 X .69 = 2.449 (2.45, loser, lethargic as you stated.)
Now back to our original thread topic.