Improving fuel efficiency with heavy vehicles
I receive a publication for the heavy trucking industry's fleet operators and the current issue had an article on 121 ways to save money on fuel. Many were applicable to RV users, some are obvious and...
Forum Discussion
royl wrote:My peak torque was at 1800 rpm stock(before headers} this is somewhere around 55 mph, mine will not downshift until 45 mph on a flat. So you are saying that I should get better fuel economy at 55 mph(max torque) than at 45 mph which to me is lugging the eng?Gjac wrote:Cummins12V98 wrote:I have always wondered about this. Can someone more knowledgeable than myself elaborate on this. I always thought that if you were in the highest gear possible at the lowest rpm while maintaining the speed you want to travel at would be your best MPG. Is this not right? Or does this hurt the eng?
"Let it lug (applies to diesel engines) "
I don't think so! That's NOT the sweet spot! Maybe BIG rigs but not pickups!
No you want to operate at your maximum torque rpm. If you look at the specs on your vehicle it will list the rpm where you are at max torque. Forget horsepower, the torque is what matters. Mine is at 62 mph and that is where I stay, if I try to run 55 my transmission is constantly shifting up and down wasting fuel.
