Technical
GM EcoTec3 truck engine GDI concerns New technology affects service practices GM’s EcoTec3 engines are workhorses, built for the tough stuff such as delivering power for hauling. This technology will increasingly be showing up in your bays, so here’s what you’ll need to know about servicing GDI (gasoline direct injection) technology. Get them back on the road, and your customers will appreciate the increased fuel mileage, power output, torque and engine longevity.
By Jeff Taylor
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Photo courtesy of General Motors
eneral Motors’ EcoTec3 family of engines is a familiar sight under the hoods of many GMC and Chevrolet pickup trucks and SUVs. It is available in three versions: 4.3 V6, 5.3 V8 and a 6.2 V8. General Motors debuted this new engine design on the 2014 model year trucks and although the 6.2 V8 versions look comparable to the GEN 5 V8 LT of the Corvette and Camaro, they are uniquely individual engines. The EcoTec3 was designed with towing,
The 2014 EcoTec3 5.3 V8 with GDI.
hauling and pickup truck grunt work in mind, not pulling 1G on the skid pad. The EcoTec3 engines introduced a tremendous amount of new technology for a truck engine and involved major internal architecture changes over its V6 and V8 predecessors. These new technologies and design changes were needed to achieve increased fuel mileage and reduced emissions output while raising power output, torque and increasing engine longevity. Compression ratios increased, intake and exhaust valves swapped locations in the cylinder head, spark plug angles changed to provide better electrode placement in the combustion chamber, a special lubrication system was designed and the engines’ fuel delivery system changed. The EcoTec3 engine was equipped with gasoline direct injection, or GDI, replacing the old port style fuel injection used in different versions for many years. GM had been using GDI in other vehicles for some time, but this was their first use of GDI in full-sized pickup and SUV applications. Directly injecting the fuel into the cylinder optimizes combustion over a wide range of operating conditions, allows for increased
22 | ASP March/April 2017
