Cummins ISX 15 Litre Operating Perametres

I was just reassigned to a truck with an ISX 550 hp Cummins. Can anyone tell me what the rpm minimum and maximum limits are on this engine? I ran Cats for so many years, and this seems to want to be treated a little different. I pull a lot of 4-6% grades, with GVWs between 85 and 105 thousand lbs. And is my top rpm climbing the same as my top rpm on a downgrade on this ISX? Thanks folks!

A little internet digging on Cummin's web site got this:

The ISX15 560-hp (418 kW) rating is now available, and generates 1850 lb-ft (2508 N•m) of peak torque. This engine rating is designed to overdeliver – with peak horsepower at around 580 (433 kW), available from 1700 rpm through 1900 rpm. Low-end performance is exceptionally strong, as it runs from 1150 rpm to 1500 rpm at the full 1850 lb-ft of peak torque.

Looks like you may get a few more RPMs out of this engine.

That's what I thought, although most of the guys I talked to kinda walked the numbers back. Thanks for the data. Don't want to limit the truck's potential when I need it the most.

This engine uses a lot of oil, and one of the guys told me it's a characteristic of these ISX's when you consistently pull the steep grades above 1550 rpm. Any information on that? I can tell you it definitely prefers the 1700 range on a pull, but after a week of doing that, I'm dumping another gallon in.

We really don't get much into the finer points of engine performance and maintenance here. This is the Cummins Engines web site. You can also search for "ISX 550 hp Cummins engine reviews".

This engine uses a lot of oil, and one of the guys told me it's a characteristic of these ISX's when you consistently pull the steep grades above 1550 rpm. Any information on that? I can tell you it definitely prefers the 1700 range on a pull, but after a week of doing that, I'm dumping another gallon in.

I know that most big diesel engines will burn oil if they are filled above a certain nominal level that varies from engine to engine. That engine might burn oil if the oil level is above 'X' point, until it gets below 'X' at which time it will stop accelerated oil burning. That's definitely an engine geek question though.

They'll take a good flogging and don't mind the higher rpm. Running the oil fields in PA and WV it was pretty common for us to be between 85 and 90k loaded with sand. The 6nz in the truck I was driving usually went through a gallon a week with the high rpm and crazy grades we would pull. We had another W9 with an N14 that used the same amount. I would imagine that you'll be fine as long as you're keeping an eye on it and changing it on a good schedule.