2004 Gmc Sierra 2500 Hd Slt Extended Cab Pickup 4-door 8.1l on 2040-cars

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Chevy's 6.6-liter Duramax is pretty much all new

To say there's a heated battle in heavy-duty pickups is an understatement, with Chevrolet, Ford, and Ram constantly trading blows of increased torque, horsepower, and towing capacity. The latest salvo is the revised, more powerful turbo diesel 6.6-liter Duramax V8 in the 2017 Chevy Silverado. It has 910 pound-feet of torque, an increase of 145, putting it nearly level with the Ford Super Duty. Here's a closer look at where those gains come from. How exactly did Chevrolet add all that torque plus 48 horsepower? The automaker essentially took a fine-tooth comb to the entire engine. Chevy says it changed 90 percent of the V8, and the cumulative effect of those small changes adds up to big increases. As you might guess, the turbocharger is updated. The larger unit features electric actuation of the variable nozzle turbine (VNT), and what Chevy calls a double axle cartridge mechanism that separates the VNT moving parts from the housing. That helps with heat performance as well, with a claim that the exhaust side of the turbo can run continuously up to 1,436 degrees Fahrenheit. Helping that cause are six exhaust gaskets made of Inconel - an nickel alloy that contains chromium and iron – and upgraded stainless steel for the exhaust manifold. Despite having the same cast iron cylinder block, albeit with some minor enhancements, the engine has new cylinder heads, pistons, piston pins, connecting rods, and crankshaft, which have all been upgraded to handle 20 percent higher cylinder pressures. Alongside the increase in pressure, Chevrolet also increased the cylinder head's structure with a honeycomb design. The pattern features high-strength aluminum with dual layer water jackets that not only improve strength, but also optimize water flow for better cooling. For 2017, the cylinder head also benefits from integrated plenum that aids the engine in getting more air under heavy loads. The cylinder head isn't the only component to get a minor update, as the pistons have a larger diameter pin for improved oil flow. The same detailed improvements has been bestowed to the humble connecting rods (second in our hearts only to the inanimate carbon rod). The new design has the bolts oriented roughly 45-degrees to the rod instead of parallel. The angle split design, as it's called allows for easier passage through the cylinder.

GM looks to combat high theft rates on SUVs with added tech

The Cadillac Escalade has been at or near the top of most-stolen and insurance-loss lists for more than seven years, until it dropped to number six earlier this year. In 2011 it was fitted with a host of new security features to address its easy-to-override features and that has brought the number of thefts down, but when eight of the ten most stolen rides are large SUVs from General Motors, no one will argue that something else needs to be done.
Thus, GM has fitted this same theft-deterring tech to the 2015 Suburban, Tahoe and Yukon. The Suburban and Tahoe will get the steering lock that the Escalade and Yukon already get, plus bolted-down third-row seats to deter thefts like this, stronger door lock cylinders and shields, and side-cut keys to inhibit picking.
Additional security measures in a Theft Protection Package can be purchased for $395, consisting of sensors on the greenhouse glass and interior, an incline/tilt sensor and added "key control systems" to make it more difficult for the men in black balaclavas to steal what you bought.

GM reportedly developing 2.5-liter turbo four-cylinder

General Motors is allocating a massive amount of resources to developing electric technology, but it's not forgetting about the gasoline-powered cars that make up the bulk of its sales. It's reportedly designing a new 2.5-liter turbocharged four-cylinder engine based on its 2.7. Citing "sources familiar with the matter," enthusiast website GM Authority wrote that the 2.5-liter four is "in [the] final stages of development," meaning it should be announced sooner rather than later (assuming the report is accurate). Technical details are few and far between as of writing. The publication learned that the 2.5 will be part of the Cylinder Set Strategy (CSS) family of engines and that it will be mechanically related to the 2.7-liter currently found in the Chevrolet Silverado 1500, among several other models. It will feature dual overhead camshafts. It's too early to tell which models the 2.5-liter four-cylinder will end up in, or how much power it will generate. The output will likely depend on the application. For context, the 2.7 delivers 310 horsepower at 5,600 rpm and 348 pound-feet of torque between 1,500 and 4,000 rpm in the Silverado. In the smaller Colorado, it provides anywhere between 237 and 310 horsepower depending on the trim level selected. While this is pure speculation, our crystal ball tells us the engine will end up powering crossovers. It's an easy deduction to make. We can't imagine it will be offered in the Silverado, and seeing it in the Colorado is unlikely because its entry-level engine develops 237 horsepower; there's likely not much of a market for a midsize truck with 200 or so horsepower. Putting it in the Corvette wouldn't make sense and the Camaro has nearly reached the end of its life cycle without a successor planned. This leaves us with Chevrolet's range of crossovers, like the Equinox, as well as their GMC-, Buick-, and Cadillac-branded counterparts. We're not discounting the possibility that the cars set to receive the 2.5 haven't been unveiled, but those are likely crossovers, too; the odds of seeing another big Chevy sedan are very, very low. General Motors hasn't commented on the report, and it hasn't publicly announced plans to expand its CSS family of engines. If the report is accurate, we should learn more about the new turbocharged, 2.5-liter four-cylinder engine in the not-too-distant future. Featured Gallery 2022 Chevrolet Equinox RS View 56 Photos Buick Chevrolet GM GMC