2008 Chevrolet Suburban 1500 Z71 No Reserve on 2040-cars

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GM patent reveals new two-stage turbocharger

Modern turbochargers may be some of the best ever made, but performance is something that engineers are always trying to improve. According to GM Inside News, General Motors (GM) is hoping to alleviate some of the negative aspects of a two-stage turbocharger setup with a newly-patented design. The patent, that was filed on May 19, 2016, reveals a clever bypass system that allows the engine, a four-cylinder unit, to optimize both the low-pressure and high-pressure inlets for its respective functions. According to the filing, a conventional two-stage turbocharger setup is engineered to allow both turbines to operate simultaneously at low and mid engine speeds. At high engine speeds, only the low-pressure turbine works. The setup can't isolate either the low or high pressure side, which can impair low-end performance. GM's new two-stage turbocharger setup looks to eliminate this by linking the high-pressure turbo to the exhaust manifold through the high-pressure inlet duct. The low-pressure turbo is attached to the high-pressure turbo by a low-pressure inlet duct, which is linked to a connecting channel. A single actuator that is housed in the exhaust manifold creates a bypass that can opens the high-pressure inlet or close the connecting channel. Depending on what the engine load and speed is, the ECU guides the actuator—a single rotating spindle with discs corresponding to flanges on the high and low pressure sides—to isolate one of the two turbos. Isolating the turbos allow the respective inlets to be engineered for the best possible fluid dynamic performance. The setup should increase performance and decrease lag. There's no word on what car this setup will make an appearance on, but it will most likely be used in premium vehicles before trickling down to the rest of GM's vehicles. Related Video: News Source: GM Inside News, AutoGuide via GM Authority Cadillac Chevrolet GM Technology Sedan turbo patent engine turbocharging

GM faces possible class action lawsuit over 8-speed transmission

General Motors has been hit with a class-action lawsuit from owners who allege the eight-speed automatic transmission found in several rear-wheel-drive Chevrolet, Cadillac and GMC models between the 2015 and 2019 model years has a defect that causes the vehicles to hesitate and jerk when accelerating or slowing down. The lawsuit was posted to ClassAction.org and spotted by GM Authority. Problems with GM's Hydra-Matic 8L90 and 8L45 transmissions have been well-documented on Internet forums and via complaints filed with the National Highway Traffic Safety Administration, with many reporting damage to their vehicles. The lawsuit was first filed in December in U.S. District Court for the Southern District of Florida but appears to have been transferred recently to New York. Autoblog sought comment from Theodore Leopold, the lead attorney for the plaintiffs. "These transmissions have a common defect," the complaint reads. "Drivers attempting to accelerate or decelerate their cars feel a hesitation, followed by a significant shake, shudder, jerk, clunk, or 'hard shift' when the vehicle's automatic transmission changes gears." The problem also occurs when the vehicles accelerate in a single gear, without shifting, the plaintiffs allege. "Drivers have reported that the shift is sometimes so violent, they feel as though they have been hit by another vehicle." The problem is believed to center on the transmission, torque converter or both. The complaint says it causes undue friction, causing hydraulic systems and gears to function improperly and sometimes leaves metal shavings throughout the transmission, leading to costly repairs and replacement of parts or the entire transmission. It says GM has known about the problems since shortly after it introduced the transmissions, and has issued 13 technical service bulletins, none of which have resolved the problem. GM declined to comment on the lawsuit. The plaintiffs say GM should have warned consumers about the issues and covered repairs under each vehicle's three-year/36,000-mile bumper-to-bumper warranty. They're seeking statewide classes in at least six states: California, Florida, Illinois, New York, Oklahoma and Texas.

Common Dodge Ram 1500 vs. Chevrolet Silverado breakdowns

These two trucks are famous for their ability to get the job done. Still, even the toughest vehicle can have mechanical problems at some time. What if we match the Dodge Ram 1500 and Chevrolet Silverado head to head? Let's find out more about common repairs for each model. Also, learn some tricks to pay for car repairs. Clunky Steering Both Dodge and the Chevy owners sometimes notice bumping and clunking when steering. This might be more noticeable when driving over bumps. The cause is usually different in each truck though. In the Dodge Ram, clunky steering is more likely due to a defective lower ball joint. Replacement costs around $300 - $400, parts and labor. Clunky Chevy Silverado steering is probably a steering rack failure. This problem appears more often in trucks with over 90,000 miles. Silverado steering rack repair will run you up to $1,000 or more. Starting Woes For the Chevy Silverado with over 130,000 miles, you might notice trouble starting. This problem may appear occasionally at first, but it typically gets worse. Excluding a weak battery, the culprit is usually the starter. Replacement will cost you around $330 - $500. Of the total cost, $90 is for labor only. Now the Dodge Ram might make a ticking sound when starting, especially on models with over 94,500 miles. The noise often disappears after the engine warms up. These symptoms may indicate a broken exhaust manifold. Repair costs range from $800 - $900. Burning Oil & Gas Gauge On The Blink Sometimes, the Dodge Ram burns oil much faster than normal. In models with over 125,000 miles, this often points towards a leaky intake manifold gasket. A knocking sound may also appear with acceleration along with possible engine misfire. The cost to repair is around $200 - $300. The Chevy Silverado has its own surprises, especially when you've filled the gas tank but the gauge still reads low. Or the needle fluctuates widely from low to full while driving. In trucks with over 120,000 miles, it's likely due to a faulty fuel sensor. You might need a full fuel pump replacement, which can cost you up to $820, parts and labor. Water Inside And Poor Heat The Ram 1500 rear window has been known to leak. You might notice the back seat and floor wet after a rainstorm. This is more common in trucks with over 65,000 miles. Resealing the Ram 1500 rear window costs around $150 - $250.