485 HP MX-13 no power pulling up hills

Try pulling in one gear lower at higher RPM and see if you keep a higher speed.
1500 isn't exactly lugging but that is what I would try.

 

What are you rear end gears? The MX engines are cruised WAY low.

 

^^^Like he said, what are your gear ratios? Otherwise, sounds like you need more torque, and if the engine has already been re-rated, and the dealer says there is nothing wrong, buy a Steinbauer module to help you make some more power. They're not exactly classified as free or cheap, but they work better than anything else out there.

 

Paccars MX13's will start pulling torque around 1200rpm. The people I know that have them said they had to basically learned how to drive these motors. The company made them watch a video from paccar to show them where the torque range is on a pull. Drivers learned that when you drop the rpms to 1200 thats when the engine will start to pull.

 

Yeah, I snagged one of the DVDs out of one of the new trucks which came in... pretty informative. I tell the drivers not to shift by sound until they get a feel for that engine.

 

That engine is a whole different breed. The torque curves are much lower than most other engines are.

 

Same thing I've heard. I know when dad bought Cascadia with DD15 not conventional 60 series 12.7 it took getting used to because quieter plus lower rpm range.