Proper truck for a very heavy trailer
I am moving out of my tour bus that I converted and into a Space Craft trailer. Those of you familiar with Space Craft will understand that it's very heavy. It's a 43' fifth wheel trailer with a...
Forum Discussion
Hoping the T part of you motor is a turbo version, as you should be able to do more than 30 mph on a 5-6% grade at 26K and 300 hp. Then again as grit is pointing out, incorrect gearing be it in the trans or rear ratio, can screw one up. If you motor is not a turbo, assuming you are talking say above 5-6000', with a 3% loss of HP per 1000' up you go, being at 15% loss at 5000, and 30% at 10000' elevation, you're going to be going slow.
There is more to pulling a trailer or moving a MH than just the power of the motor(s) being compared.
Generally speaking, as also noted, a higher number of gears with a given spec motor, you will usually go slightly faster with the 10sp vs a 6, or 4 sp trans or whatever number of gears. Alson axel ratio, and tire diam can vary this point to some degree also.
Your combo needs around 150 HP depending upon the aerodynamics of the set-up, to 30% more if not very streamlined. Then another 45HP per 1% grade you want to pull at 60 mph. You are going to need around 450HP to go 60 mph up any 6% grade at 26K lbs or there about.
Marty
It is a turbo engine in the old bus. Can’t imagine the pain of having a screaming Jimmy that can’t pull a grade.
And I’d hazard even a detuned 6.7 Cummins would out pull the lower end (power rating) ole Smokey motor.
Regardless of your penchant for calculating theoretical “grade ability” if the OP could go faster than 30mph up a hill then he probably would have said so.
Bottom line is OP needs to learn/read technical specs if sizing out a med/heavy duty truck with a particular expectation.
