I know I am taking a chance on getting ridiculed but I am hoping I can get some guidance. Just purchased a '23 GX460 with 24K miles. My question is regarding the gear oil and transfer case oil. I have decided to use 5W-30 in the engine. I know what the manual says for the gear and transfer case oil but what do you use? I want to protect my "investment" and don't care about fuel economy (if I did, I sure would not have purchased a V8). It seems some use 75W-90 for all three boxes. Some use Red Line for the transfer case. Anyways, I'd like your opinion. Oh, I did get that small filter to replace the foam one on the secondary air box. Any advice, I'm all eyes and ears.