General Motors has re-engineered the 2011 6.6-liter Duramax turbo diesel V-8 for more horsepower and torque and better fuel economy.
The re-design included the 2011 Chevrolet Silverado and the GMC Sierra 2500 and 3500 heavy-duty pickup trucks. The new Chevrolet versions made their debut at the Chicago Auto Show while the GMCs will come out at the St. Louis Auto Show.
General Motors asked customers what they wanted, took their ideas and came up with a bigger, better version of the heavy-duty pickup trucks. Customers wanted more pulling power, a more powerful diesel engine, longer durability and better fuel economy. General Motors delivered on all of these requests, plus some. The fourth-generation Duramax diesel now has what is believed to be the torque leader in its class, has an 11 percent better fuel economy than the last model and has been engineered to perform for 200,000 miles before needing an overhaul. The engine also doesn't need a block heater unless saying in temperatures colder than -20 degrees Fahrenheit. The enhanced six-speed Allison transmission can handle the higher torque load and contributes to the improvement of the fuel economy.
The truck is mostly based off of the latest models, although a lot of new parts are on the vehicle. A catalyst reduction after-treatment systems, which uses urea-based diesel exhaust fluid has been added. The fluid is kept inside a 5.3-gallon tank mounted on the frame of the truck. Refills to the tank are needed every 5,000 miles, costs $3 - $4 per gallon and can be found at truck stops and farm implement stores. The fluid is filled through a nozzle in the engine compartment. When the fluid has about 500 miles left until it goes out sensors will come on and alert the driver. Once the tank is empty of fluid, the engine will be limited to a speed of 4 miles per hour until the tank is refilled.
The newly redesigned engine is also capable of running on B20 biodiesel, which is made of 20 percent biodiesel and 80 percent petroleum-based diesel. Along with this improvement are several others worth noting: all-new stiffer frames, fifth-wheel towing capacity of 20,000 pounds, ball hitch towing capacity of 16,000 pounds, payload capacity of 6,335 pounds, improvements to the suspension for handling the towing and load capacity and larger diameter and wider width front and rear brakes. Also offered as an option on the trucks is a smart exhaust brake system. This system slows the truck and trailer on descents and is activated by the driver.
The new heavy-duty trucks from Chevrolet and GMC will hit dealer floors this summer.