Walthers 2-8-8-2 with Soundtraxx Tsunami 2

[trainforfun]

yes but some times when you let engine sit on the layout the wheels can become dirty. look how you have to clean track that has been sitting awhile.

Yes cleaning the wheels I agree 100% , but not the traction tires and all .

[ns737]

yes but in this case the engine he has has no traction tires.

[peteski]

yes but in this case the engine he has has no traction tires.

Actually, he added a "traction tire" using Bullfrog Snot.  That adds some thickness the driver's the tread diameter, possibly preventing the adjacent drivers in that engine from contacting the rails, therefore reducing the number of reliable electrical  contact points.  Most likely there are multiple causes of the poor running, and Bullfrog Snot could be one of them.