I have two 2-10-0 Spectrum Steam Locos that have no pulling power up a slight grade;  wheels slip and I cannot pull a decent load of cars.  I have looked to see if i can add weight to the engine but there does not appear to be any space available other than a bit in the tenders.

Are traction tires or Snot an option?  If so, what tires should I be looking at and where would I get them.  Do you put them on all the drive wheels or just a few?   Fairly new at this so I appreciate any help.

I recently purchased a Spectrum 4-6-0 MD and PA steam loco - DCC with Sound.........I realized no manual was included in the box.  Can anyone suggest how I can get a user guide or manual....eg., with a list of functions, etc.  Cant seem to find the right area on the Bachmann site to get one.
thanks in advance