Here's my theory - is it full of baloney? I was thinking that i should drive with an eye for maintaining the lowest EGT's. Even if the RPM's are higher with Overdrive off that would mean less fuel is being used.
When I load my camper and head for the hills i weigh at least 11,000 pounds. i noticed when going up hills that i can turn off the Overdrive and let the RPM's go higher, and the EGT's decline quite a bit almost right away.
For example: Overdrive On and a steady highway hill climb makes about 1100 degree EGT's and 2000 RPMs.
If i turn off the Overdrive the RPM's jump up to 2500 when it downshifts, but the EGT's decline down to about 950.
Those are guesstimates since i can't remember the exact numbers from the last trip.
I don't recall seeing the transmission temp change either way.
Which is the wiser way to drive?
When I load my camper and head for the hills i weigh at least 11,000 pounds. i noticed when going up hills that i can turn off the Overdrive and let the RPM's go higher, and the EGT's decline quite a bit almost right away.
For example: Overdrive On and a steady highway hill climb makes about 1100 degree EGT's and 2000 RPMs.
If i turn off the Overdrive the RPM's jump up to 2500 when it downshifts, but the EGT's decline down to about 950.
Those are guesstimates since i can't remember the exact numbers from the last trip.
I don't recall seeing the transmission temp change either way.
Which is the wiser way to drive?