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My G37S has 19" low profile tires and I am worried about over inflating them. They have a life expectancy of about 17,000 - 22,000 miles. I am worried that by over inflating them I will reduce the life expectancy too much and it will end up costing me (the tires on the car are not cheap). What are your opinions? Keep in mind I am trying to improve my FE to save money mostly.

Another Question: Anyone here with a manual trans. start from 2nd gear right off the line? Is it more efficient because you keep a bit lower RPMs?

Another: When you guys (manual transmission) cruise at 30-35 MPH do you keep your car in top gear?

Yet Another: What is better for sub 35mph cruises: keep your window open or use air vents?

Thank You.

Inflation to higher pressures (within reason) improves tread wear. My OEM tires usually last people 15-20k miles at stock pressures, and I'm at 28k with at least another 15-20k left in them. My only concern is that tires on 19" rims probably give a harsh ride as it is, and making them even harder might not be fun. But you can give it a shot and back off if you find it uncomfortable.

Use all the gears and shift early to keep the engine at moderate load/low RPM when accelerating. Keep it below 2K if you can, especially since you have that big V6.

Put the car in the highest gear that allows the engine to run smoothly. You will know if you gave gone too far when it starts to get harsh/vibrate. (I used 5th gear at 35mph in my Accord unless I was accelerating.)

Below 35mph it probably doesn't matter if your windows are open or closed. Try to keep them closed once you hit ~40mph, because that's roughly where aero drag starts to play a bigger role in FE.

Cool, Thanks. How far over the recommend pressure do you inflate? Let say the recommended is 32 psi is 36-38 psi safe? Yeah, the G37's tires are kinda rough, coupled with a hard suspense it can get uncomfortable but I don't care really.

You can safely take your tires up to the maximum pressure listed on the sidewall. For low profile tires that is usually 51psi.

17,000 miles ?

I get miffed if I get less than 60,000 miles out of a tire

What is the maximum printed on the sidewalls?

Ophbalance, look at the sidewall of your tires. Besides the size, you will see numbers for treadwear (higher the number, the longer the tires are expected to last), traction (an A is pretty good), Temperature (an A is again pretty good - it is an indication as to how fast your tires can transfer temperatures - B is less capable, C is even worse.

Keep looking around the sidewall, and sooner or later, you will see something about max load and PSI at max load. Read this section carefully, and you will see the Max pressure for your tire.

I was about to say to check the sidewall-on some cars the max is 44 psi, on some it is 51 psi.