Uphill Shifting

Thats hardly worthy of notice. I guess it's a bunny slope... but frankly if you were at cruise you wont even notice.

 

Is there a stop sign or something you have to stop for going up?

 

Every engine will be a bit different. You want to refer to your engine owner’s manual. For the DD15, you generally want to downshift between 1000-1100 rpm.

On a steep upgrade, I downshift at 1150, so my rpms fall at 1500. Technically you can downshift at something like 1400 so you fall at 1750, but I wouldn’t do it. The DD15 can, however, handle 2100 per owner’s manual, but recommends under 1900 for fuel efficiency.

For mpg purposes, you don’t want to downshift too early if you really don’t need to. You see, lower gears consume more fuel than higher gears. So if you know a particular uphill will only require one downshift at 1100, then that would be more fuel efficient than downshifting it at 1400. Sure, a 1400 downshift will have you rolling faster, but you won’t save much time.

On the DD15 with a 9-speed transmission:

9th = 3.3 mpg (full throttle)
8th = 2.3 mpg (...)
7th = 1.7 mpg
6th = 1.2 mpg

 

Why would you hold till it levels off to shift? You lose all your forward momentum when you do that