I was asking for BITOG/Actual owners reviews and opinions, NOT GM's official BS. I am fully aware of what GM recommendations are as is everyone on BITOG so I don't think this response is adding anything to the conversation.It’s right here in the 2020 Sierra owners manual which is on the net in a searchable format. Back in 2020 the recommendation was Dexos 1 Gen 2 which has been superseded by Gen 3. The OP’s question was what is brand recommended. I would choose a brand that has good internet rebates which for me means Pennzoil and sometimes Mobil. As always you will get input from thickies to disregard the manual and run a 40 grade. It’s the Bitog way.
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