New Owner Tire Question, SAFETY ISSUES?

I have 42 front/ 40 rear on my Goodyear Comfortreds, the "upgrade" from the factory Goodyear Integrities. Max psi on the sidewall of both these tires says 44 psi, so I'm right up near the max. Ride is great, but that's subjective...YMMV.

Lower tire pressure numbers on the door jam from Toyota would give you a softer ride, again, subjective to what you are used to.

It's yet another choice you have concerning the Prius. Most on this site run 42/40. some run the 35/33 (door jam numbers). Many can't stand even numbers so they run 39/37 (sarcasm). All have opinions, all enjoy their cars immensely!

 

The higher pressures will put you in greater danger of impact damage to the tire (possible blowout on violent impacts). There haven't been any reports of this being a problem, so we must be operating in a safe area.

An expert in the industry told me a few months ago the higher pressures increase the possibility of impact problems.

I run 40 front, 38 rear. Seems to work fine.

Perhaps you should invest in a nice gauge. I use an accugauge (digital). $20 at an auto center. It's consistent with another make/model and with commercial gauges.

 

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Softer tires wear faster (who does that benefit?) and give a softer ride. If your tires are circles while supporting the car then you may be dangerously overinflated. IMO you are in no increased danger if you are within the manufacturer's spec or close to it.

You are doing good out of the gate. Block your upper grill and you should be able to pick up a bit more.

 

Question: Are tires considered overinflated or dangerously overinflated if the pressure is higher than that recommended on the sidewall, or if the pressure is higher than recommended by the car maker (in the Prius-35 in the front and 33 in the back)?

 

The psi number on the side of a tire only reflects the “maximum permissible†inflation pressure for that tire.

FYI: The maximum permissible for the OEM tires are 44psi.

Keep in mind that the psi number on the side of the tire does NOT represent the "blowout" pressure or anywhere close to it for that matter. Otherwise we hypermilers would need new tires each time we hit a bump!


I've read before that the blowout pressures are usually upward around 200psi or so.

 

Overinflation is when you exceed the maximum pressure listed on the sidewall of the tire. It is HIGHLY recommended to never exceed the pressure listed on the sidewall. I would also caution against going below the pressures listed on the door jamb. Too low a pressure will cause edge wear and possible tire failure.