I have tP245/45VR18 V-rated tires on my SE that the dealer had set at 44PSI. I noticed that the proper PSI setting is 32PSI. When I set them at 32PSI the ride softened but they almost look like they are going flat.

Just curious what others have this tire PSI set at?

 

The vehicle placards and literature for almost every vehicle made suggest tire pressures that I consider to be low. At 32psi, the tread will usually wear out on the edges before it does in the middle.

Pressure is very important on low profile tires. I carry 36psi in front and 33 in the rear with 225/55HR17 tires. I would probably carry about the same with 245/45V18 tires.

I would certainly never run less than 34 in front. As 60% of the Maxima's weight is on the front, the tire will look flat with 32psi.

For me, the higher tire pressure gives more even tire wear, more maneuverability, slightly less hydroplaning in wet weather, a slightly cooler running tire in hot weather, and even a tiny boost in MPG.

 

I run 42 PSI on all four corners. I've bent wheels before and that's not cool, so I run high pressure. Not to mention it gives better performance.

The low pressure is so the car will ride better, but I'm young I can handle the "rough" ride, it is loads better then my eclipse.

 

Well, this question always gets you a lot of differing "advice" ... so here's mine:

- Pay attention to the tire placard ... the car mfr's can't afford to lay bad or unsafe pressure info on you, and the published pressures are the best compromise for handling and safety.

- Do not over-inflate your tires. That's asking for weird wear and reduced traction in wet and dry, not to mention potential safety concerns.

- Get a really good tire guage (or maybe even a couple of them, preferably the dial-type, to make sure they are fairly accurate) and check your tires frequently. Consistent pressure is almost as important as correct pressure.

Now, having said that, I personally keep all 4 of mine at 30psi (cold) all year 'round, and even when doing highway duty. At 13,500 miles, my tires are showing minimal wear, and they are scuffing in nice and evenly across the tread. I've felt the tread after long stints at highway speeds in hot weather and they run nice and cool at those pressures.

I know you high-pressure guys will disagree, but tire manufacturers say overly-high pressures will cause accelerated wear in the center tread area and will often show cupping as a result of the tire actually "dribbling" (like a basketball) after hitting bumps. Not to mention the traction-related safety issues already addressed.

Play it safe. Go with the mfr's recommendations.

Mike

 

Oh, and I meant to say, too ... the biggest thing people carped about when radial tires were introduced (and, yes, I'm old enough to remember the changeover from bias-ply to radial) was that they "looked low".

It took tire manufacturers years to convince people that they are supposed to look that way. The tire is designed to put the tread surface flat on the road when the sidewalls are slightly flexed like that, and it allows the tread to stay flat during cornering maneuvers instead of lifting one edge.

These aren't truck tires ... don't air 'em up 'til they're round!

Mike

 

What probably actually happened was that the dealer prep guy was sloppy and didn't check tire pressure. After they chain them down to the transport, they increase inflation pressure to make sure the chains are tight and the tires don't flat spot.

I would follow placard and err on the high side. Recently read a great article on tire testing in one of the mag's (sorry, can't remember which - I get four) in which the testers said it's better to be five over than three under, especially for WET traction.

 

Thanks for the great replies especially by MIKE_TX. You also have to remember when you set at 32psi and then run for a while they will heat up and add 3-4psi to readings. If you set above 40 and then get hot they are then running 43 to 44psi which is the manufacturer designed limits on my tires. Not safe at all.

 

I second MIKE_TX's advice: If you really want to accurately monitor your tire pressure, invest in a good quality dial type gage. I bought a dial VDO (German made) tire gage 20 years ago and it has served me well. When I bought my first Maxima (new) in 1990, I thought the ride was awfully harsh on the way home. Checked the pressure and each tire had over 60 lbs. in each one!

Some of the worst offenders for over-inflating tires are the people who should know better: The tire dealers themselves. I had brand new Falken 451's mounted and balanced on Velox Hyperion wheels two weeks ago and checked the pressure when I got them home. All were over-inflated to 44-46 lbs.

The tire guys all seem to use those cheesy pen-type gages with the little pop-out scale. Those things are junk and totally inaccurate. Try checking a tire more than once and you get a different reading every time. Some of them use a gage that is part of the air hose fitting. They may work when they are new, but they never check or calibrate them. Almost every new set of tires I ever bought was improperly inflated.

I have always run my tires at 32 lbs. front and 30 lbs. on the back on both of my Maximas and have never had a problem with tire wear.