Thank you everyone for the help!  I did notice we didn't have a a wheel on the engine that has a spot for a traction tire,

We have cut down the trestles so it is much lower and less of a grade, probably half as much as it was and the train is working great pulling up to 5 cars up the grade.

Thanks again.

Ohhh thank you I'll look again!!

Thank you.  I will adjust accordingly.

I'm pretty sure it's DC, but there are traction tires?  I thought the wheels have to be metal for the electricity.  They are in fact all metal

It's the SanteFe EMD FT engine.  I have an oval and I have an 18 piece graduated tressel it starts just fine at the first two tressels then bogs down at the 3/4"-1' tressel and spins, well at least I think it is spinning it sounds that way?

My engine can only pull 2 cars up hill, it sound like the wheels are spinning with more cars.  Any thoughts.  Can I use 2 engines?