All tracks must have an underside grouser bar on each track plate for gripping the surface of the tyre. Where this grouser bar is worn (on old tracks) or lubricated (as when driving in wet peat or clay conditions), slippage between track and tyre can occur. Tyre slippage can also be a problem on very large, high horsepower machines which are heavily loaded and working on steep, wet, sloping ground.
The dimensions of the track underside grouser bar are very important in order to avoid tyre slippage whilst ensuring no tyre damage. If the grouser bar is too sharp or aggressive, tyre damage will occur. There is therefore a very fine balance to be achieved for the shape and dimensions of this grouser bar.