Boxster S oil for Texas?

[old911doc]

Remember, in the oil viscosity rating, the first number relates to the oil's behavior when cold, the second number to it's behavior when hot. Think of a 0W40 oil as a somewhat-thick oil that doesn't thicken further when it is cold. It's a 'viscosity 0' at cold ambient temperatures, i.e. Winter, but a 40-viscosity at engine operating temperatures.
I run 0w40 Mobil 1 in Alabama with good oil pressures across the range of our temps, down to 20F on winter mornings, up to 103F on summer afternoons.
An alternative to the pricey Mobil 1 might be Shell Rotella T6,a full-synthetic oil, available in 5W40 for $135 for a 5-gallon bucket, sometimes on sale for $105. This oil is primarily intended for Diesel engines, but what makes the most difference in engine lubrication and resulting engine life is viscosity and CLEANLINESS. I've never seen an engine worn out by excessive oil changes.

[lkchris]

Your motor is going to run at the thermostat-controlled temperature whether you're driving in Texas or Maine. Maintain your cooling system, of course. Your engine generates most heat not in Texas, but when the motor is working hardest, e.g. on a top speed extended Autobahn run. You'll never do that, but your car's cooling system can handle that.

Porsche A40-spec oils are all synthetics, and with synthetics there are no temperature problems ... basically your only concern is starting a cold engine and how cold ambient temperature is at the time.

A few years back I read Mobil specs for all their synthetics ... there was no difference in cold pour point between 0W, 5W, and 10W. Iirc, all were -55 F. 15W-50 was a few degrees warmer.

40 is 40 no matter what the W number is. Etc.

Follow owners manual; don't worry, be happy.