Your tire pressure

Some of my tires markings are very clear that to use the full tire load rating, you are REQUIRED to inflate it to that marked sidewall pressure. Lower pressures mean lower permitted loads. Otherwise you are asking for trouble.

Cars have do have a lighter max load rating than their tires, but many people ignore these load limits.

These tires also expressly forbid seating the bead with anything more than 40 psi.

 

My understanding is this is a one-time only action.

Bob Wilson

 

Bob, I sure love looking at all your graphs and pics. I don't think I've understood a single one of them but they sure are purty. In fact, I think they'd make a nice coffee table book.

 

Hummm, I'm used to dealing with graphs and tables of data. Is there any one aspect you'd like to cover in more detail?

• ROLLING DRAG
• TREAD TEMPERATURE
• WHEEL ALIGNMENT

I have no problem with taking any one section and using both the graphs and text, explain what is going on.

Bob Wilson

 

46/44 psi with OEM tires, 15" wheels.

What is the maximum side pressure for the OEM Yoko tires in the 15" wheels? Maybe I'm putting too much air...

 

Ok tire experts, what is my optimal pressure -

I am at 42 in front, 40 in back. My max pressure is 51psi. The tpms did work for me and the light went on with a tire at 31 psi. I am not sure at what pressure the tire distorts to start lifting the edges off the pavement. I know that there are diminishing returns on milage after a certain pressure. I have continental ExtremeContact dws 205/50R17.

 

On my old 2004 Prius I had 44/42 with the Integrity tires. I bought new Fuel Max's in June and was able to put 52/50 in them. We took it on a 4 week road trip in July and they were great tires. The Fuel Max is rated at 51 psi.

I traded the 04 for a 10 in November and I have these tires at 44/42.

When I'm asked about the high pressures I have to say that when you ride a bike, what pressure would you rather ride with? Low tires require a lot more energy to roll with, the Prius is no different.

Have you ever noticed that the wear of tires with the recommended psi always seem to wear on the edges, proof that the psi should be a bit more.

 

Even at 45psi I had some edge wear on the 15" Integrities on the 2006.

 

Double check the max sidewall pressure and use that at the top number. Otherwise, you're in the same region I use.

Bob Wilson

 

The nice thing about radials is they tend to have a stiffer 'foot', the tread area in contact with with road. Under inflation is bad but it really is hard to over inflate ... but maximum sidewall should always be treated as the upper limit ... if nothing else for insurance purposes.

Bob Wilson

 

OK, but how do I check the max sidewall pressure?

 

I think the easiest way is to look carefully at the sidewall and try to read those tiny figures. In the North American market, one of them will say what the maximum tire pressure is for that tire. There is lots of neat information on the sidewall of tires. Much of it is in code, which can be decoded fairly easily but the max pressure is in plain language.

If you are curious, google "sidewall tire markings" and you will get a link to Tire Rack which explains exactly what each of the markings means and where it is on the sidewall.

I would give you a link, but I am not all that skilled at that.

 

Your just fine where you have them, especially with your highway drives.

Wayne

 

After installing new tires yesterday and driving around at 35psi I can honestly say I don't know how you guys do it. I felt like I was sailing a tuna boat because the ride was so unstable and mushy.

 

Did you install the same Yoko OEM tires?

 

Not sure what you mean. My car never had Yokohama OEM tires.

I've had:

Goodyear Integrity
Kumho Ecsta ASX (17")
Nokian i3
Yokohama dB Super E-Spec

All three of the above 15" tires have been run at 35psi and they all felt terrible. It's just been so long since I have experienced the feeling that I forgot how bad it was. I usually have them set at between 48 and 60psi.

 

I see, you don't have the 2010 Prius... I was talking about the same tires that comes standard in the new Prius... max psi is 44. I agree 35 is too low but I also feel it is too rough at max side pressure, but I use max anyway for better FE.

 

Amazing to me is how many people hold this view, and who also exceed the maximum speed limit on the road.

The dangers of speeding are well documented, and there are those who insist that driving the speed limit is more dangerous for all kinds of reasons. How about driving around with 10, 20, 30 gallons of gasoline in your car?! Good lord. Probably best to not go outside...

 

No question speeding contributes to car accidents but the major problem is that people don't drive defensively. There are too many gadgets, distractions, or people are eating or doing other forms of multitasking while driving. I believe the statistics show speeding coming bellow distraction, fatigue, and drunk driving. Some parts of Europe are classic for having lower than average accidents even in high speed areas but drivers are typically more defensive.

If people just pay attention all the time to the road and try to forsee upcoming threats, the accident rates would lower dramatically...