Shifting RPMS

Good luck finding a single answer.

JMO forget shifting intervals run them up tight, and grab the next... you'll never see fuel savings there. You best to keep RPM in sweet spot for Hwy, and adjust for torque/HP in hills.

 

ugh... Wha?!
progressive shifting saves fuel. it's been proven time and time again. so much so that every single truck engine maker has programmed their ecm to allow a truck owner to force drivers to use progressive shifting by limiting the rpm in each gear.

 

and dis-proven by many too. When you have an experienced driver in the seat, the amount of fuel wasted is overtaken by knowledge, and not puter controls. Show me your fuel charts and maybe I'll consider it, otherwise the fact is yes it does dump fuel, but not enough to register in a 200 gal. measure w/ over a .0+ percentage. We have found it so insignificant that it is no longer programed. And further found experienced drivers got their savings more on deceleration.

 

I wind my Cummins up to 1900 at least and never noticed a loss in fuel mileage.
I feel that shifting at to low of rpm is lugging the engine too much and that will not save fuel either.
My 10 speed runs out of gear in 9th at 70 mph so when i hit a hill i'm down shifting from 10th to 9th at about 65 mph.
It pulls pretty good at 1800 rpm.

It all depends on what engine and gear setup anyway.Everyone has a different shifting style.

 

an experienced driver that cares will always do better than a computer, that has no bearing on if progressive shifting saves fuel or not. winding an engine to max rpm before shifting is just wasting fuel and putting extra unnecessary strain on a drive train.

 

your 100% correct, gas on it b4 a hill! what you do in the hill has more to do w/ milage than simple take off. Long hills know your truck and what it'll do. you may gain/loose some depending on setup, but for most part I don't like bottom end of RPM range under stress... If I own it I'll be shifting lower, reguardless of fuel, and try to make it up on downside of hill. Co. owned w/ fuel bonus I'll be hanging tight @1050 and rocking in my chair to help it up the hill. LOL

 

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I completely bombed my reading comprehension of your previous two posts.. my bad. that will teach me to read forums while shopping for school shoes for the kids.