After it became clear that General Motors' new line of 2011 heavy-duty Silverado and Sierra trucks was actually a more powerful line than Ford's, the company was scrambling to up the ante on its existing line.
Ford announced in August that it would give free upgrades to truck owners and it is working to up the muscle in its diesel engine. Truck owners will be getting letters explaining how they can upgrade the power of their trucks by October.
The new upgrades make Ford's F-250, F-350 and F-450 engines capable of 400 hp and 800 ft.-lbs. of torque, pushing the numbers past the 397 hp and 765 ft-lbs. of torque on the turbo 6.6-liter GM Duramax.
In a statement to the Associated Press, Ford's Anne Marie Gattari denied that GM's lineup was the reason behind the power changes, instead saying testing proved the horsepower and torque increases wouldn't compromise engine durability while citing an end to a contract with its former diesel supplier Navistar International. Ford has resumed engine production in-house.
GM said it was very confident in the performance of its line and encouraged the public to test both brands.