Thinking about increasing tire pressure to 36 PSI to save gas, is it too much?

Bullshit. That is simply not possible. You can not get a 4 mpg increase in fuel economy with a 2 psi increase in tire pressure. That defies the laws of physics and the billions of miles of carefully controlled tire testing that have been done over the last century buy rooms full of guys with engineering degrees and very expensive test equipment. I suggest your test criteria are highly inadequate and you are fooling yourself. Those clever guys with the automotive engineering degrees and the huge test tracks that designed, built and tested your car know a lot more about what the BEST tire pressure is for your car than you do. I would go with what they recommend.

Your nissans tag says 32psi.That reccamendation is based on many factors. Your nissan came with max 35psi tires from the factory and allowing for air pressure increase from heating up the tires from driving is aprox 3 psi. Now you have 44psi max tires on the car. These new tires have a stronger construction and can hold the higher pressures you want to run without effecting the tread contact pattern therefor not effecting the safty issue. Running 36psi shouldl not hurt handeling or safty. Todays tires are made to be run closer to their maxx pressure but allow for heat psi expansion, usually 3 to 5 psi.

The problem with changing the nominal pressure is the tread profile. At the design pressure, the tread is flat with the road surface. YES, your MPG increases but that is because of less contact of the rubber with he road. Your BEST MPG would be gained from a knife edge tire which has the LEAST surface area in contact with the road. THEN, hardness... the harder the tire, the less energy in deformation as the tire rolls, and again, less energy lost into deformation of the rubber in the tire. Railroads get so many miles per gallon per ton because the tires do NOT deform and the area of contact is SO small. When railroads say they get 500 miles per gallon per ton, they speak TRUTH. But then, they have the ideal; minimum surface contact, minimum deformation, minimum rolling friction. When it comes to YOUR tires, the closer you come to the railroad ideal, the better your MPG, but the lower your measure of safety. Increasing tire pressure lowers your tread footprint, lowers your rolling friction, but also lowers the safety quotient as well... So, you get better MPG at the expense of your safety... Are you SURE you want to risk your LIFE, your safety for a trivial gain in MPG???

32 psi if the correct psi for your tires, although 35 psi is what most shops and people inflate too. I keep mine at 35 psi above that is not a mpg issue, it causes a rougher ride, youll feel for flaws and bumps in bad roads.

Your Continentals or Michelins, depending which option 2.5S you have, should not be pushed passed about 35psi. Any more than that will cause them to wear prematurely. Sticking with your current 34psi will get the best of both worlds with good fuel efficiency, crisp handling, decent wear, and not too rough of a ride.

And you've been using the two pounds extra pressure for how long? Sorry, one tankful does not qualify as sufficient data. Come back when you have a year's worth. (If you're reading this off the dash display, don't come back at all: we know you're kidding.)

rowlfe said it right 34 will be fine but 36 maybe too much