[trikkonceptz]

Adding my experience to the story,

When I began hypermiling with my Vibe I was careful to make one change at a time and watch the changes to see if it was worth the modification. I can absolutely attest to the MPG increase once I raised the tire pressure from placard to 50 psi cold. Now with my increase I used the nitrogen product in order to keep the pressure stable as the tire temp increased.

I did notice a harsdher ride, but I also witnessed improved traction when cornering, (No squealing tires) and improved wet weather traction, (no hydroplaning). In line with that I saw a nice 3mpg bump in mileage.

Now I also believe that in order to save money manufacturers use the tire as an additional dampner in their suspension design to make cars roll smoother.

I say this because I also have a vehicle that has a very low profile tire. 225/30/20. These tires have to run at higher PSI because sidewall flexing results in breaking of the bead and destroying a rim. In addition I spent some serious coin and bought an adjustable coil over suspension for this vehicle and had it professionally tuned for proper height and dampening.

WOW !! this vehicle rides likes a serious luxury car with nothing felt as far as bumps. In fact if I do not remind myself that i am 2 inches off the ground I will rip my bumper off the car accidentally. That proved to me that a properly engineered suspension can do its job properly despite the tire and independent of it.

Its just too many companies count on soft squooshy tires to act as a suspension instead of the suspension doing the work.

Also and I saw no mention of this in this post. There is no money in replacing tires every 80K miles or more. Dealers make more money off of parts and service than the sale of the car. Ergo, a tire that wears faster means more trips to the dealer for new tires and other related services.

I would also like to add that I have no data on better braking for the simple reason that our driving habits tend to teach us to brake very little and respond to changing road enviroments much sooner than later. I also have the added benefit of owning a vehicle that has ABS and traction control which negates the need to skid all together.