After hearing people regarding my oil change interval using amsoil series 3000 (six months regardless what milage i have, roughly 7500 miles) im thinking on using synthetic blend instead. Would schaeffers oil be my best option? Ive been reading some uoas on this oil and they seem really good. Also should i stick with the 5W30 or use their 5W40? Redline was used for most of my trucks life then i switched to amsoil. Im thinking schaeffers would be the best bang for the buck in a good way. Thanks. Oh yea i have a 2002 Tacoma V6 with 55K.