mtfrizzell
I don't know if you would be able to add traction tires without replacing the two front drive wheels with wheels grooved for traction tires.
Some folks use a product called Bull Frog Snot applied to the wheels instead of a traction tire.
I have used bathroom silicon sealant applied to a wheel as a traction tire.

Before doing any of the above,  I suggest that you try adding weight to your locomotive.
I have a couple locomotives that "should" be good pullers but are not because they are not heavy enough to have good traction.
I use fishing weights, set on the locomotive pulling the number of cars that I want to see it pull, to measure how much weight I need. 
Then using sheet lead I find places to spread the weight out inside the shell, out of view.

Can't find sheet lead? make your own using a hammer and anything that can be used as an anvil, to pound flat fishing weights...


Happy Rails!
Dave