I started writing a book for CANADIAN owner-operators with tips on how to get into trucking but I"m not sure if it'd help you if you're from US. You can also check my trucking blog where I describe how I got started with my own stepdeck trailer I'm leased to a Canadian flatbed carrier and spend 95% of my trucking time in US.

My truck is a simple International but I put a lot of money into the engine: right now it's a 550 HP 2,000 lb-ft CAT C15 Acert with 3.42 axles. I cruise around 62-63 MPH and average 6.5 MPG, depending on the load weight and terrain.

 

Sorry for off, but i didn't know you could have 2000lb torque with 550. Just 1850lb. Is it something new, or you are simply mistaken?

 

I've done lease/purchase on two trucks, and outright bought one. Seems like the most popular transmission you can get your hands on these days is a straight 10 speed. Really not a bad tranny, and I've pulled a whole lot of freight with them.

Of the trucks I've driven, I've gotten good fuel economy with two of them. But the key seems to be in the rear-end ratio. With 3:55 and 3:73, the economy was crap. With 3:42 and 3:43 (with 22.5 tires) the economy ranged from the low 6s into the high 7s. Depending on the load, terrain, and wind direction. Running westbound across NE (into the wind) and getting 6.7 miles per gallon was nothing to sneeze at in my book. Not when other guys were telling me they were getting 4 and 5. My best mileage was with a 3406 CAT and an N-14+ Cummins. Both rated at 500 horsepower.

Buying a truck today, things to look at besides fuel economy (a very big issue, without a doubt) are durability and cost of repairs. Cat is one of the highest on repair costs, not to mention the fact that Cat is getting out our engines. Good service, but not much future. Cummins seems to be a bit cheaper to have repaired than Detroit, and I had far less problems with the Cummins than any Detroit I've ever driven.

So, if I were going to spec out a truck to buy today (instead of collecting my Social Security), I'd be looking at a Cummins, about 500 Hp. Either a 10 or 13 speed, and rear ratio somewhere around 3:40 to 3:48. I've found that 3:42 drops you right about in between gears at double nickle. But, in normal running, the lower you are able to get the rpm, the better the fuel economy, as long as you are not lugging the engine.

Wife and I pulled a load of laminated redwood beams out of OR. Going up one of the hills, we passed a 500 Cat and really impressed the owner of that truck. Our fuel economy on that load was around 6.5.

 

That's what you get when you have a CAT and can afford to pay $800 to a CAT dealer for Dyno tuning

HP = Torque x RPM / 5252

Hence,

Torque = HP x 5252 / RPM

According to the paperwork I received after the Dyno, my Kitty Cat makes 550 HP at 1,425 RPM, so

550 x 5252 / 1425 = 2,027 lb-ft or torque!

The resulting torque is so high because my CAT develops all this horse power at very low RPM (1,425 instead of usual 1600). Needless to say, I love my CAT.

 

OK. Thanks. I'll check it out, tho I'm quiet satisfied with 1850.