They face a new challenge this week when a client asks them to turn a Ford F550 into a hard-hauling 6x6 farm truck that's also a rolling showcase for biodiesel fuel. And Diesel Dave and Heavy D make their dreams come true when they build the first diesel Monster Jam truck.

This episode will air on Monday, August 20 at 10 p.m. PST/EST.
 

For more information, visit discovery.com.