Using the trucks cruise control while loaded?

Hrm. I find the opposite, at least in a manual transmission.

As long as the engine is pulling smoothly and not lugging down, I keep the cruise on. My truck will pull smoothly in top gear at @80k down to about 45 MPH @ 900 RPM.

I let the truck keep pulling in the highest gear as long as possible because low RPM efficiency in highest gear is much more efficient than moderate RPM efficiency in the next lower gear.

In my truck's case, with summer fuel, top gear fuel usage never goes below 3.5 MPG. The next lower gear will instantly drop my MPG to around 2.7 MPH if I switch.

Diesel engines are more efficient in the low range of their healthy operating range. I believe this is universal to all standard large diesel engines.

 

Mmmmm. I have 7.3 mpg for lifetime of truck at 600,000 miles.

 

If u have a auto trans i could set the cruise at 6t and never turn it off and pull every hill in the west region , these auto trucks basically drive themselves its incredibly boring

 

See from what all I've read, I think if you're not flirting with 9 in a new truck with an auto, you may have wasted your money. Truck 2 gets 8+ all day at 65 to 68. 3,25 rear end. It's a '16 though, mines a '12 with3.55's, but I only cruise at about 62.

 

Man im lucky to get 6.5 pulling flatbed , i got 7 in my 9 speed , this auto they pawned on me is junk .. Not to mention it is #### at shifting, i like to laugh at it when it messes up and tell it " see thats why u let me shift , cuz i actually know how !" lol i know every once in awhile my company gives me a van to run when they are stacked with freight and flatbed is slow and ive been able to get 8.5 , i would agree tho , why waste money on junk if ur not getting 9mpg, im not even sure the added money saved in fuel economy even pays for the repair bills when the frickin thing breaks

 

@Mandeepsingh how long have you been driving trucks?

 

What I was saying was that your fuel economy is better with the hammer down and low RPM when hill climbing, as opposed to dropping a gear and running at a higher RPM.

Edit Add: As long as you are still in the healthy pulling range for the engine.

 

Can almost bet that didnt happen. But maybe he will be back for some tutelage by you.

 

What kind is it?

 

Its a dt12 in a 16 cascadia, ive had more problems with it than i care to remeber , some guys say its the best but idk mine is in the shop every couple months for tranny issues