W900

What tire size?

 

That Cummins rep doesn't know what he is talking about. Peak torque comes in just below 1,200 rpm. You can take it to that rpm and it will be just fine. I've even run the Efficiency series down to 1,000 rpm cruising. They will survive just fine.

 

You say the Cummins rep doesn’t know what he’s talking about, well I’m here to tell you it will not pull a greasy string out below 1400

 

https://cumminsengines.com/uploads/images/engines/x15-performance-torque-curve.png

 

I've run up Eisenhower so many times running 1300 rpm in one and it does just fine.

 

I'm not talking about running it down to 1200rpm on a pull, I'm talking about running it under 1400rpm at cruising speed for long periods. I'm sure the Cummins rep doesn't know what he's talking about.

 

Congrats on your new ride! You wont be disappointed with the engine.

 

I understand that, and like I said earlier it will still do the job just fine. There is no issue with running it at that rpm while cruising on the highway. The engine will still make enough heat for the aftertreatment at that rpm so you are good there and the engine life will not be affected by running it at that rpm either. That Cummins rep is just misinformed. It isn't like I've spent the last four years of my life working on and driving trucks with that engine in them.