My 2017 GMC Sierra 5.3 calls for 75W-85 front and back differential oil, but I’ve seen other people recommend Valvoline SynPower Transmission & Differential Gear Oil 75W-90. Any other opinions?
I’ve used 75W-90 in my truck without any issues. It offers better protection at higher temperatures.
Valvoline’s a good brand. Just make sure it meets the GM specifications for your differential.
75W-90 can be a good alternative, but always check your owner’s manual for specific requirements.
I’d stick with what the manufacturer recommends, but if you can find a good deal on 75W-90, it should be fine.