2004 Gmc Sierra 2500 H/d on 2040-cars

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'Killing a Duramax' Gale Banks YouTube series methodically tunes a diesel to death

Learning or perfecting a skill by watching YouTube videos is known as attending YouTube University. GM Authority picked up on one of the video site's more fascinating courses, hosted by Gale Banks; in a fair world, he should be referred to as Professor Banks when it comes to diesel engines and truck tuning. A few months after GM introduced the updated L5P 6.6-liter Duramax diesel V8 in the 2020 Chevrolet Silverado HD and GMC Sierra HD that ships with 454 horsepower and 910 pound-feet of torque, Banks decided he wanted to methodically tune the engine to death. The purpose of the resulting series, called "Killing a Duramax," is to push more power out of the engine in order to discover which parts break and when — or, as Banks puts it, force-feed the Duramax "until the crank hits the street and the heads hit the hood." With that knowledge, Banks can figure out all the weak points on his way to building what he calls a "Superturbo," that being a supercharged, twin-turbo race engine with more than 1,000 hp. What makes the series fascinating is Banks' knowledge, paired with the company's comprehensive iDash engine monitoring system that keeps tabs on a glut of parameters every step of the way. So for instance, you get Banks explaining the differences between inches of mercury and barometric pressure, how those are different from the water content of the air measured in grains, then showing those readouts on the iDash, then explaining in detail how they affect the air density in the Duramax system. The stock Borg-Warner variable turbo gets a lot of airtime — Banks accuses it of being "out to lunch" because he feels it's the weakest link on the engine. That turns into a turbo teardown and a deep explanation of performance pitfalls, such as when air pressure on the turbine begins to diverge from the boost pressure coming from the compressor. Banks says he can keep close tabs on where power's coming from, because the iDash monitors the horsepower contribution provided by the ambient air, the turbo, and the intercooler separately. The major changes so far are a stouter Precision 7675 turbo and TurboSmart wastegate (episode 5), a twin intake (episode 6), a custom liquid-cooled intercooler from a marine engine, a new GM oil cooler and synthetic oil (episode 10), and new injectors (episode 11).

370,000 new Silverado and Sierra pickups recalled over fire risk

General Motors announced late Friday that it will recall around 370,000 Chevrolet Silverado and GMC Sierra fullsize pickups from the 2014 model year over a possible fire risk. The recall covers select 4.3-liter V6 and 5.3-liter V8 models, which can evidently suffer engine compartment fires due to the overheating of exhaust components. GM notes that the fire issue may be preceded by a check engine light and an "engine power reduced" message on the driver information display.
Thus far, GM is aware of eight fires stemming from this problem (although only three of those incidents affected customer-owned vehicles), and all of the fires were reported in areas with "very cold weather." GM is urging owners to not leave their vehicles unintended while idling. No injuries have resulted from the fires in question.
The Detroit-based automaker has pledged to start mailing out recall letters on January 16. The fix, which involves software reprogramming, is estimated to be a 20-minute repair, and will be made free of charge.

5 things we love about the 2019 GMC Sierra AT4

NEW YORK — The 2019 GMC Sierra AT4 proves that GM's upmarket truck and SUV brand is getting serious about offering rough-and-tumble capability to rival the Ford F-150, Toyota Tundra, Ram 1500 and Nissan Titan. Until the Sierra AT4 rolled onstage at a media event in lower Manhattan, prior to this year's New York Auto Show, the GMC brand had been more focused on luxury touches like fancy chrome wheels and posh interiors — no surprise, considering the upscale SLT and Denali trim levels account for the vast majority of GMC sales. So now GMC wants to get muddy and adventurous? Well, yes and no. The AT4 adds hardware that'll take truck buyers off the beaten path, though this GMC isn't anywhere close to being a Spartan, no-frills work truck. To better explain, let's look at five key features we love about the 2019 GMC Sierra AT4: More than stickers and chrome The Sierra AT4 isn't a cynical marketing ploy, there is some true all-terrain toughness built into this pickup truck. A factory-installed lift kit raises the AT4 by two inches, while Rancho monotube shocks, a locking rear differential, a two-speed transfer case and standard all-wheel drive prove this GMC can dare to venture off paved surfaces — though you might risk getting mud and muck on the truck's handsome 18- or 20-inch alloy wheels. Power and economy The Sierra AT4 comes standard with a 5.3-liter V8 coupled to an eight-speed automatic transmission. In the standard Sierra 1500, this engine produces 355 horsepower. GMC didn't mention engine specs here in New York, though it's possible the AT4 might get a small power bump. This engine should be plenty for most truck buyers, though GMC offers two tempting alternatives. These include a turbo-diesel 3.0-liter inline-six, along with a 6.2-liter V8. Both motors are paired to stop-start fuel-saving systems, along with a new 10-speed automatic transmission. Carbon fiber cool factor The GMC Sierra's available carbon-fiber cargo bed, called CarbonPro in GMC-speak, trims 62 pounds of weight, as compared to a traditional all-steel bed. This slick feature uses carbon composites for interior panels and, judging from GMC's videos of burly bricks and huge hammers being thrown into a CarbonPro cargo bed, it should prove more than up to the task of ... well, having someone throw bricks and hammers into the cargo area.