The factory specs are for the front and rear are 29. That seems a bit low to me and I usually run my stock tires at 32 and havent seen any problems with tire wear or ride quality.

I was reading on another forum (MercuryMarauder.net) about how inflating the tires above the the recommended PSI to around 40 or 45 really helped with the uneven tire wear handling and mileage.

What do you guys inflate your tires to and what are your thoughts?

 

I have mine in at 34/30 f/r I like the extra crispness in the ride plus the steering is sharper. Im not sure if there is extra wear on the tires, but 205/65/R15's are cheap tires compared to what I had before so it doesn't bug me.

 

43-44 psi all around...

 

At winter time I would go with 29psi (unless you want to ruin your winter rubber).
At summer time - go ahead with 31-32psi.

 

i go with 33 all around. i bought my tires from costco, and they say they use nitrogen, and claim that it doesnt "inflate" when the tire gets hot, like regular air does.

 

since air is a gas it expands when heated and contracts when cooled, this means that it should be checked before you drive or before rising temperatures (the tire making contact with the road) or the sun's radiant heat affects it. always keep your tires to their max psi,(that's what their made for) if u don't u will be suffering from uneven tire ware and bad gas mileage, tires are made to hold their max psi, printed on the side of each tire) and a lot more becuase of heat.
nitrogen doesnt expand like air... , but is that good?

 

Try not to post when you know little about the subject at hand. The max pressure printed on the side of the tire is exactly what it is.... MAX PRESSURE. It's NOT optimal operating pressure! Optimal tire pressure is figured by the size and type of the tire PLUS the car it's on.

alpicone, 32 psi is just fine. You should always follow what the manufacturer suggests. 29 to 32psi is just fine if you are on stock tires. If you have the pressure too low or too high, you will get uneven tire wear. The numbers that you see are always measured cold. You'd be surprised how much pressure can rise after you've driven for a few minutes. So, check the pressure in the morning when your tires are cool.

 

well of couse listen to aron... because im a fool.
-i was just told different.

-i posted like 100 times today, bound to F*k somthin up.
thanx for stayin on top of me and putting me in my place.

 

Nitrogen is a gas , when you heat a gas it expands, if it is contained in a closed space, your tire, the pressure increases.
Air is 80% nitrogen.
The guys at Costco would fail high school Physics,
and probably did.

Google Avogadro's principle if you want to boggle your mind.

 

they also claim that it does not allow rusting of the rim, as oxygen CAN do.

 

Read this: http://www.mtdealer.com/t_inside.cfm...t&storyID=1207 and then make your decision

 

Post what you know, not what you were told or heard. If you do reference what you were told or what you heard, then be specific and mention that. That is how bad info gets propogated.

 

Read and be informed. http://auto.howstuffworks.com/question594.htm

 

Too far from my High School physics to give an authoritive answer but have some questions,
1) Is the tire evacuated of air when they fill with N?
If not then you still have Oxygen in the tire as well as water vapor.
2)Are rusting inside of rims a common problem?
3) Normal air pressure at sea level is about 14.9 lbs a square inch.
How much nitrogen proportionately would be put in a tire of X size
to raise the pressure to 30 pounds? Evacuated and not evacuated?

Don't bother to answer. Just thinking in pixels.

Maybe it makes a difference in handling, but I doubt I would notice.

 

i just inflated my fronts to 45 PSI and my rears to 50 PSI. I originally had all four at 30 PSI

 

35 psi all around for me.

 

His principle just states that at a fixed temperature and pressure, any gas contains the same number of particles.

You sure you don't mean Charle's law where pressure is proportional to temperature?

 

Keeping front and rear pressure closer to equal is important, as it ballanced the handling characteristics of each tire, making either end of the car similar, which should help in ballancing the car altogether. A couple pounds here and there, trying to increase the crispness in the front end and such is up to you.

As for the factory specs, you do want to stay close to that. Keep in mind those specs are relative to tire size, so they can only be used on that particular size. With upgraded tires, consult the manufactuerer or the installer. Generally it's going to be in the 30-40PSI range, I think my Maxima recommends 28PSI and I'm running around 33 or so. It will vary from tire to tire, and from car to car. If one size and type of tire works great at a particular pressure, on a different car is may or may not work as well with that same pressure due to the weight of the car, that's why there are specs on the car in the first place. Therefore it's relative, and not fair to say a certain pressure as definitive.

The only think I can think about for nitrogen is volume and deterioration. Nitorgen is quite dence so you can fit a lot of it into a small space and it should yield good ride characteristics, but like stated above it's 80% of what you're breathing right now so the effects are minimal. The tires and wheels can deteriorate from air, and nitorgen will help with this.

 

32 front, 29 rear on stock tires, 38 all round on 17" summer tires, but I was still playing around with pressures a little bit, so it may not stay there. I've ditched my stock tires too, and I'm not sure what I'll set the winter tires that replaced them to yet.

29 PSI is the minimum you should run though. You can go up in pressure, but not down.

Another supposed benefit of nitrogen is that it is a larger molecule (N3 I think?) and doesn't leak or diffuse out of the tire as easily.

 

is it good to have my tires at 45/50 PSI?

 

i have 45 psi all around... no problems.. ever...
thought that was just the way it had to be

 

It all depends what type of tire you have. performance tires usually need more psi that regular tires. Best way to find out what your recomended tire pressure is to look on the sidewall of your tire. The psi rating is written there.

 

yeah, mine are performance summer tires. And the max pressure as read on the sidewall is 51 PSI

 

most tire manufacturers say to check the pressure when cold. they know the pressure will increase with tire temperature. i have stock rims and "standard" tires and run the fronts 4 pounds higher than the rears. this gives me nice even wear from edge to edge. the pressure i use depends on what the tire is rated for. if the tire is reated at 36 max, i use 32/28 f/r. if the rating for the tire is 44 max then i use 40/36 f/r. i don't beleive in exceeding the max air pressure, the ride is too rough for the old bones.

 

Umm..... NO. Definitely not.

The pressure on the sidewall is the MAXIMUM pressure, not the recommened pressure. It even says it is the maximum.

Ask the tire shop you got them from (or any one maybe) for a PSI suggestion. There is a guideline for how many PSI you are supposed to increase the pressure when plus sizing, but I don't remember off the top of my head.

At 45/50 you are likely near the maximum pressure for those tires and you probably do not have to run them that hard (unless you carry heavy loads a lot).

 

HEHEHE to Funny

 

33 all around

 

i remember the day i bought my yj jeep with my dad, it had big ole 33 mud swampers on it, the ride was incredible smooth, and then i checked the psi in the tires, it was like 16 psi all around. nucking futs. oh and i go with dennisMik, hes smart.

 

all this is very informitive, but what if i stole the tires off my brothers acura because i'm to cheap to buy new ones, and they are 205/60/R15 instead of 205/65? still run around 40 psi, or go lower/higher because a smaller sidewall? right now i'm running 42 because that's what the place that changed the rims and put the tires on filled them to

 

I usually run either 35 all around or 45. My tires are 195/50/15

 

look at the sidewalls on your tires and inflate a few pounds lower than the specified max psi, to allow for air expansion

 

Max pressure that is written on a tire is there for load rating purposes only.....follow manufacturer spec.