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Small block engine power for GM pickup

GM has re-engineered its classic Small Block engine with the new EcoTec3

pickup truck

GM’s claim to fame in the pickup market is that its trucks last the longest of any brand, which is based, it says, on a survey of registration data. You’ve probably heard it make that claim in marketing and advertising for a long time. That longevity claim may apply even more strongly to one of its engines. The 350 small block that has been the mainstay of GM pickup engines has been around forever, it seems. And it’s still one of the most commonly used engines by those who modify or build their own vehicles.

“Small block engines have been used, abused, modified and raced in almost every type of car and truck imaginable,” says Jordan Lee, global chief engineer and program manager for small block engines. “Our engineers are able to draw on that experience to build stronger, more efficient, more dependable engines for Chevy truck customers.”

GM says the EcoTec3 engines used in today’s Silverado pickups are direct descendants of the original small block V-8 design, and they benefit from more than 60 years — and more than 100 million engines’ worth — of continuous improvement.

“The latest small block engines are ideally suited to Silverado and to the tough jobs that pickup customers do every day,” says Lee. “We give customers the power and torque of a full-size truck engine when they need it, then use Active Fuel Management and other advanced technologies to seamlessly shift to four-cylinder operation when the truck is under light loads, making the most of fuel efficiency.”

GM’s Active Fuel Management technology turns 10 years old in 2015. The brand first introduced it in 2005. All of the engines available in the Silverado this year have the option of taking advantage of that fuel saving concept.

For 2015 GM gives full-size pickup buyers a choice of three of its latest small blocks, known as the Gen 5. First is the 285 horsepower, 4.3-litre V-6, which puts out 305 pound feet of torque and has a U.S. EPA rating of up to 24 m.p.g. Next is the 5.3-litre V-8 with 355 horsepower and 383 pound feet of torque, topping out at 23 m.p.g. highway. Lastly, the 6.2-litre V-8, which is no slouch, with 420 horsepower and a torque rating of 460 pound feet. It gets up to 21 m.p.g. on the highway.

GM says it puts engine designs through a series of durability tests that help engineers develop and verify the strength of its components. During development the engines endure severe thermal cycle testing, which quickly cycles the engine between extreme cold and hot coolant temperatures to validate the durability of engine components such as the head gaskets and exhaust manifolds. Then, there is the “hot scuff” test, in which a brand-new engine is run at wide-open throttle with no break-in period, helping test critical engine parts such as bearings, piston ring sealing and bore scuffing. The Active Fuel Management system gets tested too. It’s forced to cycle in and out of the cylinder-deactivating feature hundreds of thousands of times at a variety of engine speeds.

If you opt for the 6.2-litre engine in a Silverado this year, you will get the all-new 8L90 8-speed automatic transmission bolted up to it. The 4.3- and 5.3-litre engines are matched with GM’s Hydra-Matic 6L80 six-speed automatic transmission. The 6.2-litre engine and 8-speed transmission combo will give a Silverado a 12,000 pound (6,000 kilogram) trailer towing rating. GM also offers an available trailer towing package, which features a 247.9 mm (9.76-inch) rear axle, heavy-duty rear springs, revised shock tuning, enhanced cooling and an integrated trailer brake controller. Wider trailering mirrors and better back-up lighting are also an option.

Last year GM introduced a long list of updates from the frame to new body styling, which carry over into this year’s models. But there are still a host of other new options and features for 2015.

The 2015 Silverado is offered in WT (Work Truck), LS, LT and LTZ trim levels, along with Z71 and High Country models. All three cab styles and box configurations are available in WT, LS and LT trim, with LTZ reserved for double and crew cab models. WT models get black bumpers, door handles and outside mirrors. Chrome bumpers are standard on LS, LT and LTZ trims.

For the ultimate in connectivity, GM’s MyLink is available. It offers OnStar with 4G LTE and standard built-in Wi-Fi hotspot. That creates a mobile Internet hub for vehicle occupants. The hotspot is on whenever the truck is on. Buyers get a three-month, three-gigabyte data trial.

About the author


Scott Garvey

Scott Garvey is a freelance writer and video producer. He is also the former machinery editor at Grainews.



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