Quick drive oil question to you Yamaha guys. I've been operating my 2002 Stratos with a 90hp Yamaha outboard with zero problems for a few months now. I've only owned and operated Mercruiser inbd/outbd previously. Is it ok to use quicksilver drive oil in the lower drive unit? I have a bunch of this oil is the reason I ask. I know Yamaha makes a lube but I'd hate to throw away all my quick silver. Thanks..