it won't be under 50 mpg till you're making a large style of short journeys - from the define of your employing conduct i'd anticipate around 60 mpg. some early Prius had hardship with the gas injectors, inflicting gas financial equipment to drop into the 30s (that era Prius frequently have been given 40 5 mpg), yet i haven't heard of it with later generations. nonetheless, a bottle of gas injector air purifier is a robust concept. Sam's club isn't good tier gas, and which could make a huge distinction over the years. 87 octane is real, however. I switched to good tier manufacturers (first source) some years in the past. the different attention is the thermostat could be vulnerable, battling the engine from thoroughly heating up. The Prius in specific is very delicate to engine termperature - lots so as that while we've been given our first I drove around with the domicile windows open and the warmth each and each of how up one iciness to make certain what would ensue, and the gas financial equipment dropped from 50 to twenty-5 mpg for theat 5 minute era.