Hi F8L, I usually check them about once a month. I expect air loss as the temps get warmer and if we have a warm spell then a cool down, I'll definitely check them since I know that'll cause a pressure loss. Really? Hmm, I'll have to give it a shot. I think I'm only daring enough to go to 40/38 though. EG Toyota recommended that I keep the tire pressure the same on all 4 tires. Their reasoning was that because we have a toddler, a car seat, and cargo associated with him, we should add the extra 2 psi to the back tires to compensate. What are your thoughts on that? I can see doing that on our LA trips since we're usually pretty loaded down with luggage, but the rest of the time? Yes, some of my best mileage on LA trips was because I was daring enough to go slower (or traffic was nasty enough that I got out of the left lane and used the right lane more to avoid the constant speed up and slow downs between 55 and 85). My best mileage going to LA was 48 MPG, that was going 75 with a tail wind. Another time when I had a tail wind, I used it to my advantage and did 80 and still pulled off about 46 MPG. Given the fact that I have traveled between Sac and LA several times a year for the last 5 years, I know what to expect for my mileage, even worst case, and 36 was WAY too low so I knew something was wrong.