What is the optimal operating range on the newer isx engines. It seems to pull hard below 1500rpm
The tri-drive heavy haul rigs with the X15’s are geared to run at 1700RPM at 65 MPH. That seems to be the sweet spot. IDK about the ISX ‘s. They all self-destructed. Those old haul road auction trucks are pulling a wagon up in Kansas, I'll bet.
All depends--on intended use for specifications, X15 has a long flat torque curve mimicking the DD series. Also whether it is equipped with AMT or manual transmission because that can change rear drive ratios which are typically tall gears these days. Our otr's run 1400 at 65 mph rated at 565 hp 1850 torque, normal ranges are 1200 to 1650 rpm. Some 600 hp are 1650 to 2100 depending on gearing/use.
Not sure what it has for gears. It runs an 18 speed. If I wind the rpms up much higher than 1500, I can almost skip gears. My last real dealings with Cummins was when they were beige. Im told that all the tractors run an ixs which I know nothing about. The valve cover looks to be 16 inches wide. They have a Detroit in that new tractor with the amt, not sure why they wouldn't keep them all the same. They also have a cat with the twin turbo. Im old school, I shift by sound. But if I wind her out, I pretty much have to shift 2 gears at a time. Or have a long pause between shifts. I will say they do haul well. Im grossing around 49500 kgs or 109128 pounds, and rarely drop more than 1 gear on long grades. Anyway only 1 more weeks of hauling and the spring weight restrictions are on.
Maybe it is an x15. The truck is a 2019
15