Battle of Darkmount Pass
From Transformers Wiki
The Battle of Darkmount Pass was a battle between the Decepticons and a smaller group of Autobot Wreckers, which occurred some time after Bulkhead left the Wreckers for Team Prime.
Fiction
Prime cartoon
The Decepticons initially gained an advantage due to numerical superiority, and forced the Wreckers into the smelting pits. However, Wheeljack managed to single-handedly destroy all the Decepticons, and used their backsides as stepping stones to escape the pit. Con Job