after speaking to a few people at a few Caltex's i have found out they are getting their 98 octane through Mobil (same as peak) as caltex and mobil are owned by the same parent corporation so their fuel isn't a true 98 octane as it contains toulene to boost it to that level and it deteriorates over time so ya fill ya car up with 98 octane by the end of the tank its down to 95 /96 octane