Cart linking is a system added by Railcraft that allows carts to link together to become a train. This should work with any cart from any mod, all that is needed are Minecarts and a Crowbar. Note that the Crowbar will lose one point of durability per use.
Linking carts
Position two Minecarts on the track next to one another.
Shift right-click one of the carts to be link. The string "Link Started" will appear in the chat box.
Shift right-click the second cart to link. "Link Created" will appear in the chat box if successful. If "Link Failed" appears, move the carts closer together and try again.
Block Signal· Distant Signal· Dual-Head Block Signal· Signal Capacitor Box· Signal Controller Box· Analog Signal Controller Box· Switch Lever· Switch Motor· Signal Receiver Box· Signal Interlock Box· Routing Switch Motor· Signal Sequencer Box· Dual-Head Distant Signal· Signal Block Relay Box· Railway Ticket· Golden Railway Ticket