thermostat on vmax and best oil to use

[sbckinglovetexaslakes]

2 questions: do we need to change the thermostat's yearly??? we do the water pump but thermostats can go out to. saw it at the shop on another guys boat. and they are not that much to change out.

also what is the best oil to use. not trying to start a war either. I have a 1999 vmax 150. for life of the motor and for fuel economy and so forth what is the best oil. yama lube or what. i have been using yamaha oil but dont know what is the best. thanks for any input.

[boats.net]

Yamaha recondmends every 200 hours or yearly on water pump and thermostats. All we sell is the Yamahalube but it is good oil, we have never had any problems with it.