I do have a 489 carrier with 3:73’s, had these in with my 340. I was under the impression the extra torque of the 408 would more than make up for the gear change but not sure that it feels like it. I do a fair amount of highway driving
3.23 with a 408 is similar torque to the ground to a 3.55 geared 360, basically a 408 allows you to run one gear step higher than you would with a similar 360.
or about two steps with a 340, does it pull as hard as your 340 with 3.73 gears?
