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GM opens official investigation into C8 Corvette transmission leaks

In March 2020, a month after Chevrolet began customer deliveries of the 2020 C8 Corvette, a GM dealer technician created a Reddit thread about a leaking gearbox in a Corvette with 32 miles. That car hadn't even been sold yet. Since then, as a search of "C8 Corvette transmission leak" shows, it's been tales of woe for some owners. Something in the Tremec TR-9080 transaxle in the back of the mid-engined Corvette doesn't work as it should, the fault able to cause codes that the transmission needs service, or that the driver needs to shift to park. In some cases, the battery would die because of follow-on issues after the initial transmission code, that code preventing the car from powering down. As Autoevolution reports, GM filed paperwork with the National Highway Traffic Safety Administration in August to look into what's going on. Between forum threads and GM's investigation document, there are several issues mentioned. The most common appears to be the dual-clutch transmission leaking fluid due to gasket failures like the one suffered by one owner at 858 miles, and another for an owner currently enduring a second leaking transmission. The Midengined Corvette Forum reported that Chevy engineers redesigned the TR-9080 pan, fitting Corvettes with the new unit at some point in the 2021 model year. The original pan was stamped steel unit affixed to the engine with two studs and 13 bolts, plus "reinforcement plates." The updated pan is said to be a cast aluminum unit affixed with two studs and 17 bolts, omits the reinforcement plates, and gets a new machined new groove around its edge to seat the gasket seal. The GM paperwork now at the NHTSA mentions a P1789 code, and says one reason for it could be "debris on the park position sensor magnet causing an incorrect position reading to the TCM." This might be caused by another issue mentioned in forums, which is clogged transmission filters. GM gives instructions for returning transmission filters to the company, and a poster on one forum said the Corvette tech at the dealer where he bought his Corvette told him the automaker "requires every used transmission filter to be returned to GM."  Whatever's going on, the problems haven't stopped, and they go beyond the P1789 code. Over the weekend, a 2022 Corvette owner posted on Corvette Forums that he got a check engine light on his car after just 850 miles.

GM will compensate SUV owners for fuel-economy error [UPDATE]

General Motors will offer debit cards to owners of some of its crossover SUVs after it was discovered that GM overstated the vehicles' fuel economy on window stickers, Automotive News says. GM will offer reimbursements to about 135,000 customers that are worth between $450 and $1,500 each. Some owners will also have the option of being provided with an extended warranty free of charge instead of the debit card. GM overstated fuel economy on about 170,000 vehicles by one to two miles per gallon because of what it has said was an inadvertent error stemming from not factoring the impact of emissions-related hardware into the EPA window-sticker figures. As a result, GM put a temporary stop-sale on the Chevy Traverse, GMC Acadia, and Buick Enclave before switching out the window stickers on about 60,000 vehicles. Automotive News says letters and debit cards will be sent out next week, and Reuters is estimating that the reimbursement program will cost GM about $100 million. With automakers ranging from Hyundai/Kia to Ford to, more recently, Volkswagen and Mitsubishi being ensnared by emissions or fuel-economy-rating issues, GM is working quickly to address the problem. For those curious, the reimbursement totals, factoring in current gas prices, the SUVs' combined fuel economy, and typical driving of about 12,000 miles a year, will provide between three and 12 months worth of free gas for those drivers (the models get either 17 or 18 miles per gallon combined, depending on front- or four-wheel-drive configuration). While about 135,000 customers will be reimbursed, Automotive News says the fleet buyers of about 35,000 crossovers haven't been addressed yet. UPDATE: GM spokesman James Cain, in an e-mail to Autoblog on Sunday, confirmed that the company will reimburse about 135,000 customers. Purchase customers will be given the option of a pre-paid debit card or a 48-month/60,000-mile protection plan, while lease customers will be offered the pre-paid debit cards. Most of the cards will have a value of between $450 and $900 on them. "We want all of our customers to have a great ownership experience, so we designed this reimbursement program to provide full and fair compensation in a simple, flexible, and timely manner," he wrote.

GM readying aluminum-body fullsize pickups

Ford's extensive use of aluminum in its 2015 F-150 is a big deal. A really big deal. Big enough, in fact, that General Motors is reportedly changing its fullsize pickup strategy. According to The Wall Street Journal, The General has locked in partnerships with Alcoa Inc. and Novelis Inc. - companies that will supply aluminum for the next-generation Chevrolet Silverado and GMC Sierra trucks.
"Ford's introduction of the 2015 F-150 pickup truck was a game changer, and it's the first, not the last, conversion of this type," Novelis spokesperson Charles Belbin told the Journal. The switch to aluminum has allowed Ford to shave roughly 700 pounds off its fullsize truck's curb weight. And while official mileage ratings have not been announced, the weight loss should go a long way for improving efficiency, especially when combined other efficiency-minded improvements including better aerodynamics and new, turbocharged V6 engines.
Of course, aluminum-bodied cars are nothing new. But extensive use of aluminum in a major, best-selling product like the Ford F-150 is expected to kick off widespread use of this weight-saving material as availability rises and cost decreases. The WSJ reports that GM had originally explored the idea of moving to aluminum pickups back in 2008, but abandoned the idea due to cost concerns amid economic woes.