Hi. Hope I put this in the right place. I have a '98 school bus with a 175hp t444e in it and it weighs 9200lbs empty. It drives fine but doesn't climb hills well. If it hits a moderately graded 2 mile hill at 55-60mph, it will be down to 35-40 or so by the top. I had the HPOP changed as it was only producing about 1300psi but the power has not significantly improved. The turbo pressure is slightly low but not showing any other signs that it is bad.The mechanic said to chip it next but I don't know if I should. What are the downsides of chipping it? What about "power modules" instead? The dealer is checking with Navistar to see if I can uprate it. How much of a difference could I expect if they reprogrammed it to 210hp. I'm not looking to add tons of power, I'd just like to be able to climb hills while loaded at 55-60mph. Any help or ideas would be greatly appreciated.

 

I would see about refashing the PCM and if that doesn't work add a chip. There is no down side that I have found if you install it properly