Don't forget the 1st mistake most people make when calculating MPG. Most will fill their tank, calculate MPG from the miles they drove on that tank. This is wrong, you need to wait until the NEXT fill-up to see how many miles you drove and then figure MPG for the previous tank. Otherwise all your calculationa will show data from the last tanks fuel grade and be completely innacurate. Did that make sense? <img src="/forums/images/graemlins/confused.gif" alt="" /> <img src="/forums/images/graemlins/drunk.gif" alt="" />

I have about 2 1/2 years data on my '04 4x4 SR5 V6 TRD fill-ups and my best mileage is mostly achieved with regular (cheap) gas.

Higher octane is designed to essentially burn slower and at a lower temperature. So in an engine that is not high compression (e.g. the Tacoma) higher octanes can actually finish burning fuel while/after the exhaust valve has been opened. This isn't really harmful, but it can cause a reduction in power and in MPG.

I would honestly like to do more testing with my Taco and different octane levels, but with the high gas prices I think I'll stick with the cheap stuff which works just fine. <img src="/forums/images/graemlins/cheers.gif" alt="" />

Later, <img src="/forums/images/graemlins/patriot.gif" alt="" />
DC