can any one tell me fuel economy on pet 386
63" Engine Specs Cummins Engine Type ISX Horsepower 485 Transmission 13 Spd Check for Over Drive Yes Engine Brake Yes Suspension Pete Low Air Leaf Ratio 3.55 Tires 22.5 Wheels All Aluminum Wheelbase 235" Front Axle Lbs 12,000 Rear Axle Lbs 40,00
or
Cummins Engine Type ISX Horsepower 550 Transmission 13 Spd Check for Over Drive Yes Engine Brake Yes Suspension Pete Low Air Leaf Ratio 3.36 Tires 22.5LP Wheels All Aluminum Wheelbase 248" Number of Rear Axles Tandem Front Axle Lbs 12,000 Rear Axle Lbs 40,000
thanks

 

I will say 6mpg but there are alot of variables:

What kind of trailer do you want to pull?
Drive in the mountains or plains?
You going to drive 63 or 85?
How much do you idle?

 

dry van or reefer i will drive not more then 70(65) i will try not idle , some mountains some plains (west and south sometimes east)
thanks

 

Cummins or Caterpillar which one is better ?
thanks

 

What year is it? Did you mean 550 CAT? Does it have a full fairings, including roof? You also could get an ECM printout, which will tell you what is their MPG is up to date...

 

Cat, in my opinion.

 

it's Cummins 2009
i thinking to buy a new truck . I don't have family and i hope i can earn many for truck and mortgage for my condo
thanks

 

thanks

 

Well, than i can't say...I'd go with 550, gearing seems to be all right for what you are planning to do. Make sure you'll get a full fairings, and don't drive it as a race car. Should be able to achieve between 6 to 7mpg, depending on the loads, and your driving habits... But that's just a guess, I'm not familiar with cummins, especially after the last "modification". Personally I'm a CAT person, but since they are pulling out of trucking business, you might have a better luck with cummins. I hope you know, what you are doing, cause times are really tough...Good luck!

 

I would expect close to 7 mpg as long as you keep your foot out of it. Personally, I prefer CAT. Cummins makes a good engine. Either should serve you well.