What are you trying to pull with it? What kind of track are you using? How steep are your grades, how sharp are your curves? All of these things are important. The scale Turbine is a huge locomotive! If your trackwork isn't perfect, all of the wheels may not even be touching the railhead.
Also, did you check that the wheels on the tender turn freely and aren't creating extra drag? The Turbine tender probably weighs as much as your 4-4-0!
There are folks who specialize in cutting grooves into the wheels, and adding tires. They perform this as a regular service. Personally, I despise rubber tires and prefer a little wheel spin when starting a heavy train. Let's try to cover the basic issues above before we get into modifying the loco.
