Brace yourselves, but I'm kind of an oil snob. Not very bad, just kind of. I will use Amsoil and similar in certain applications but otherwise just try to stick with any given brand name which has the best price. Well, today I broke my rules. Just picked up a new-to-us Tahoe and trying to get some fluids baselined that likely are very overdue. Actually, now that its done I can attest that they were well over due. Still need to get the transmission and rear end done but did manage to squeeze in transfer case, brakes and front dif. Well, seeing as the front dif will very likely only see use during severe winter weather I did want a synthetic 75w90 instead of 80w90. And seeing as it shouldn't see a ton of miles of use per year (front axle disengages in 2HI), and that I already am spending too much on this truck, I didn't want to spend an arm and a leg on fluids. Well, hello $5/qt Supertech gear oil. Looked like gear oil, smelled like gear oil. Half the price of Valvoline Synpower. Has anybody run this stuff long term? Would you trust it for a full factory spec change interval? I figure with the sludge that came out it HAS to be an improvement and maybe I'll just change it again next year with some nicer juice...