Rawze.com: Rawze's ISX Technical Discussion and more

Im new to the isx engine and new to this forum. I just bought 2 2001 Volvo trucks with ISX 450 hp motors cpl 2628. Ive done searches on here and the ISX as well as technical documents sections. Im not finding much info on the pre egr cm570 motors. Id like to at least get the rpms up to 2000 but if it can do it safely id like to get some hp too. I'm the only driver, I pull my heavy equipment to and from my job sites. Usually less than an hour each way. gross weight is 94,000 with my heaviest piece. They only have 10 speed transmissions and 370 gears. Maybe I just need to change my driving habits, but I feel like i'm pulling it down too low when I have to shift at 1700 so it comes in down around 12.

sounds to me like your rears are geared wrong for what your l=pulling. you should be at least 4.36's or higher on that kind of operations... your engine is the last thing you want to make work harder, it is the most expensive thing to repair and replace... re-gearing it is far cheaper than trying to make the engine work harder.

classic case of the wrong specs for the job.

if the trucks are going to always be loaded heavy i would recommend a trans swap to 13 or 18sp the 500rpm swings in a 10sp are brutal with those kinds of weights.