Despite numerous complaints on the 8-speed unit.
The 2020 GMC Sierra 1500 has quite a number of engine choices going for it, ranging from the lower displacement 2.7-liter turbo, all the way up to a 6.2-liter V8 depending on the trim level you're going for. There's even a 3.0-liter turbocharged diesel six-cylinder for those looking for torquey goodness. These engines are mated to a set of six, eight, and ten-speed automatic transmissions, again, depending on the options you tick. But a certain engine configuration will soon be left with just an eight-speed auto, and it's the rather popular naturally aspirated 5.3-liter V8 L84 gasoline engine with DFM.
Gallery: 2020 GMC Sierra 1500 AT4 Diesel: First Drive
According to the guys over at GM Authority, this downgrade isn't actually reflected on the website just yet. That is, not entirely. This specific downgrade applies to all variants of the 2020 GMC Sierra 1500 in 4WD equipped with said 5.3-liter V8, despite the option to go for the 10-speed exists in the online configurator. It seems that GMC will allow dealers to take on orders of the 10-speed auto option, but then revert it back to the 8-speed transmission and just give $200 in credit on the invoice. And, according to GM Authority, it'll be like this for the rest of 2020 when it comes to that specific Sierra 1500 configuration despite not having any official announcement.
save over $3,400 on average off MSRP* on a new GMC Sierra 1500
Any quick trip to a forum or in the comments section about the rather controversial eight-speed auto is filled with some eyebrow-raising stories about transmission shudder, transmission failures, part replacements, and warranty work.
So you can see why this could be an issue for those looking at picking one of these trucks up. It seems that either there are some supply issues at work with regards to the more reliable 10-speed auto, or does GMC have an incredible surplus of eight-speed transmissions that they're just looking at dumping them in their vehicles? No news on whether or not this downgrade will continue into 2021, but here's to hoping that the 10-speed becomes the standard soon.