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n8911

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Indiana

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Message Posted: May 29, 2011 7:25:10 PM

I am looking for some good answers to this. The sticker on the inside of my door says the recommended tire pressure is 35 psi, when i look on the tire it says max psi is 41 psi. On my other car the inside of the doors says 30 psi and the tire says max is 51 psi. Are you supposed to go by the inside of the door or what is on the tire?
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HotRod10
Champion Author Wyoming

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Message Posted: Sep 27, 2013 5:08:06 PM

The door sticker pressure is the car maker's recommended for the smoothest ride without overheating the tires. The maximum on the tire is the highest safe pressure for the tire. Anything in between is ok from a safety standpoint.

Most people see improved mileage at a 3-5 psi over the door sticker and don't notice a harsher ride, but do report stiffer cornering, with less body roll, which seems like a good thing. At more than 6 psi over the door sticker, most people find the ride rough and the handling poor, with loss of traction being the primary complaint.
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dassfg
Champion Author Fort Worth

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Message Posted: Sep 22, 2013 8:17:10 AM

The door sticker is the minimum air pressure to run (remember to check tires cold). I usually run about 3 pounds over that number on car tires. Truck & SUV tires depend on their rating and weight you are carrying.
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hyeglenn
Champion Author Fresno

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Message Posted: Sep 22, 2013 7:50:30 AM

45
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Guile69
Rookie Author KW

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Message Posted: Sep 21, 2013 12:57:55 PM

Warmer months i run a pound over spec in winter im under by 2lbs for added traction
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Alien6500
All-Star Author London

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Message Posted: Dec 12, 2012 12:03:54 PM

door sticky as well
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mrbrit007
Rookie Author Denver

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Message Posted: Nov 18, 2011 2:37:40 PM

My take on this is door sticker plus 2 psi - to save the TPS turning activating on cold days.
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shanti016
Rookie Author Riverside

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Message Posted: Nov 15, 2011 1:59:21 AM

door sticky
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foreyearrunner
Champion Author Illinois

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Message Posted: Nov 9, 2011 6:04:27 PM

I go by the inside of the door, but go just slightly above that. During the winter, I fill a few more above the door
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RalphHightower
Champion Author South Carolina

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Message Posted: Nov 7, 2011 6:34:45 AM

use the door sticker
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dvc2
Champion Author Oakland

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Message Posted: Nov 6, 2011 11:33:02 PM

door sticker
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hiker_boy
Rookie Author Utah

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Message Posted: Nov 6, 2011 9:32:33 PM

I go with the door sticker
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dontuknowOH
Champion Author Ohio

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Message Posted: Nov 6, 2011 9:07:22 PM

bfa1974; is that pressure to account for road surface lean/drainage tilt? To balance the vehicle a bit to level,or account for a heavy driver? LOL Sorry, maybe a h... passenger?
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sweeteddy
Champion Author Indianapolis

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Message Posted: Nov 6, 2011 5:15:36 PM

dont have a guage
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B_550i
All-Star Author Seattle

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Message Posted: Nov 6, 2011 2:19:17 PM

I go +3
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Mothus
Veteran Author Atlanta

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Message Posted: Nov 6, 2011 2:18:26 PM

whats on car
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bfa1974
Sophomore Author Wisconsin

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Message Posted: Nov 5, 2011 7:02:40 PM

I would put one side 30 and the other side 35 psi
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ricebike
Champion Author New Jersey

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Message Posted: Nov 5, 2011 3:13:57 AM

iuhoosiers, you may want to post it on your local forums...

but if you're in my area of NJ, Sunoco, Citgo, and Quick Check gas stations offer free air
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Minges
Veteran Author Ohio

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Message Posted: Nov 5, 2011 1:47:15 AM

Yes ,right preasure saves gas!
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iuhoosiers
All-Star Author Indiana

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Message Posted: Nov 4, 2011 11:04:37 AM

Anyone know of gas stations that still offer free air? or have they all switched to charging?
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the1roadhog
Champion Author Atlanta

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Message Posted: Nov 4, 2011 9:30:33 AM

I go with the door info.
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russells350
Champion Author Montreal

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Message Posted: Nov 4, 2011 9:07:45 AM

Better to go with what is on the sticker on the door!!
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eccerr0r
Champion Author Fort Collins

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Message Posted: Nov 3, 2011 3:31:44 PM

Door rating. The car manufacturer treats the tires and the car as a system and selects a pressure for optimum lifetime and SAFETY. Pressures on the tire do not consider the car it's put on.

It's not a very good idea to run thing, like tires, at the "MAX"imum allowed pressure, that sounds like something waiting to explode...

If there's a "recommmended" pressure on the tire, that's OK to go with. But most of the times it's a "maximum".

Donut spares are the only things I can think of that actually have a fairly high pressure that you should pump the tire to.
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Honda_919_Biker
All-Star Author Lincoln

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Message Posted: Oct 31, 2011 10:51:07 PM

Always go by the tire rating.
The door sticker is really only useful for the orig equip tires and they always state a lower number to supposedly provide a smoother ride.

The closer you are to the MAX pressure, the lower your rolling resistance, which provides a higher mpg. But a rougher ride.
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orden
Champion Author Chicago

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Message Posted: Oct 31, 2011 1:39:53 PM

I use the manufacturer recommendations
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WSU_Coug
Champion Author Boise

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Message Posted: Oct 31, 2011 8:27:28 AM

on tire
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Z12
Champion Author Toledo

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Message Posted: Oct 30, 2011 6:32:49 PM

Vehicle door
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pinbuster2005
Champion Author New Hampshire

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Message Posted: Oct 30, 2011 2:24:15 AM

If you don't keep the tires at the pressure the automakers recomend on the driver's door placard then you can void the warranty of the tires if something happens while on the road.
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RRBC
Champion Author Victoria

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Message Posted: Oct 30, 2011 12:48:32 AM

good advice. I wish gas stations didn't charge for air.
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stopforgas
Champion Author Mississippi

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Message Posted: Oct 29, 2011 11:34:15 AM

I've always used an old rule of thumb. If you want a smoother more comfortable ride go with the recommended pressure. If you want the tires to last longer and don't care about a little rougher ride, go with the higher pressure.
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PaylessKY
Champion Author Kentucky

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Message Posted: Oct 29, 2011 10:57:07 AM

I go by what is on the vehicles placard.
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mcpa
Rookie Author Pennsylvania

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Message Posted: Oct 27, 2011 10:07:09 AM

I use the manufactor recommendations
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dontuknowOH
Champion Author Ohio

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Message Posted: Oct 26, 2011 11:36:02 AM

I bought a sporty car new back many years ago,it came with undersize wheels and tires 2+4 rated sidewall at that time. If you ran the pressure in those tires that the door recomended the car stability suffered, the tires sidewalls simply would run/roll under,rather fold over on hard cornering from the rims on blacktop,showing wear also.

I hated those tires,still had an alignment shop check the powersteering for defects,balljoints/sway bar,idler assembly etc. I had to change to 14" wheels/tires to correct the problems,traded in on a later model 5 years later,loved that vehicle wish I had it back. Not the original tires or the wear.
I haven't had any tire problems since about 50 years ogo GREAT!
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tattoo666TX
Champion Author Texas

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Message Posted: Oct 26, 2011 7:41:15 AM

It was not a question about checking the amount of air in the 4 tires, it was how much should be in them. Always go with what is on the label on the inside of the drivers door. Even if you pull into a good tire shop that will check and add air if needed (for free) they will look at that label, not what it says on the tire. That was one of the biggest problems with the Fords that were having roll over problems. People going by what it said on the tire.
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xtremecheap
All-Star Author Arkansas

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Message Posted: Oct 25, 2011 11:03:24 PM

The max psi on the tire is ONLY there to tell you what the maximum load can be applied to that tire. The more psi that is put in a tire the more load it can carry, but if you exceed what is posted on the tire it will likely blowout.
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dontuknowOH
Champion Author Ohio

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Message Posted: Oct 25, 2011 8:33:20 AM

Just for the sake of being nosey, why don't you call up 5 of your buddies whom you know of having tire pressure guages,invite them over to your house and then have each take a pressure reading of one of your vehicles tire pressure(same tire for each ones reading) all 5 persons doing their own test and then compare the results.

Most likely the 5th reading will be 1-2 lbs. lower than the others? It would be better to pick a vehicle that has fairly large tires to start with. also one that has been recently driven. Please Let us all know the results! Have a pizza party maybe,use whatever guage each person have bought for that purpose. Thanks.....
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WahlyIA
Champion Author Iowa

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Message Posted: Oct 25, 2011 7:54:59 AM

35psi
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pjaugustine
Rookie Author Tennessee

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Message Posted: Oct 24, 2011 4:53:51 PM

I had heard if you go more towards the maximum you get better gas mileage?
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pmjwright2
All-Star Author British Columbia

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Message Posted: Oct 24, 2011 1:08:39 PM

PS if you ever have to check or adjust PSI on warm tires (it happens, right?!), the formula is easy:

Warm PSI = Cold PSI + 4
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pmjwright2
All-Star Author British Columbia

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Message Posted: Oct 24, 2011 12:58:28 PM

Just bought a 2011 Altima...reading the owners manual last night, it says the usual. But it also states that the door label shows the "recommended cold inflation set by the manufacturer to provide the best balance of tire wear, vehicle handling, driveability, tire noise etc."

It's only a RECOMMENDED level.

One page of my manual says it's the "MINIMUM recommended pressure" (that's the first time I've seen this statement). Anyway, what that means is it you have the freedom to choose a PSI anywhere between the door label and the sidewall max.

Many other posters have explained why they choose something in between. I want better FE, so I go with the door label + 5 psi.
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ColoradoPapa
Champion Author Colorado

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Message Posted: Oct 23, 2011 5:33:29 PM

I try to keep mine 2-3 pounds over what the door label says.
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Sipusa
All-Star Author Sacramento

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Message Posted: Oct 23, 2011 2:13:45 PM

My sticker indicates 32psi but I usually keep the pressure at 35 psi.
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JimBlake56
Veteran Author Akron

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Message Posted: Oct 23, 2011 1:19:13 PM

On an acedemic, theoretical basis, you should inflate the tires until they have just the exact "designed" amount of deflection where the tire meets the road. A heavier car will require more pressure, lighter car less pressure, to get that same "proper" amount of deformation.

That's too difficult for normal mortals to measure on a weekly or monthly basis. So use the tire sticker in the car, owner's manual, door-jamb, wherever it's located. NOT THE TIRE SIDEWALL. The sidewall pressure is maximum, and it relates to the heaviest car that's allowed to use that tire.
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NEPA390
Sophomore Author Gasbuddy

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Message Posted: Oct 20, 2011 4:11:16 PM

Depends. If you want the factory ride for everyday use the door. But if you loading up a big load use the max. I run different psis all the time in my f250 depending on what i am doing with it. Off roading one pressure, Towing or having 4K in the bed max tire. Normal every day driving the door pressure.
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10on3
All-Star Author Ocala

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Message Posted: Oct 20, 2011 8:56:11 AM

36 PSI
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xtremecheap
All-Star Author Arkansas

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Message Posted: Oct 20, 2011 12:38:10 AM

On the door should get you in the ballpark. That psi number is calculated by what the auto weighs at each corner and what the original equipment tire manufacture brand recommends for that tire size. Each tire manufacture brand should have a chart for what is the best psi for the weight it is supporting. The problem comes when the tire is replaced with a different brand that did not come on the vehicle from the factory, or when weight is added to the vehicle. The not so easy solution is to have the vehicle weighed at each corner with any added weight that would be carried under normal vehicle operation. After that weight is recorded find the corresponding psi that the tire manufacture recommends.
Now the easy way that anybody can do. Fill the tires to max psi on tire, take auto to closest, level parking lot with a piece of chalk. Let the tires cool as long as possible so the reading will be accurate as possible. Take the chalk and mark a straight line across the tires. Drive the vehicle in a straight line for several car length and the inspect the chalk line. If the chalk is worn off in the center as it should be because they were filled to max psi, it has to much air. Let out a few psi and repeat the process until the chalk line is worn off in an even pattern across the tire. If the chalk is wearing off on the inner-outer edges, it needs more psi. Record the even wear psi and you should be good to go until you change tire brands or size or add more weight to auto. Also if the chalk is worn off at angles then an alignment is probably recommended.
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Kado101
Sophomore Author Oklahoma

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Message Posted: Oct 19, 2011 10:57:26 PM

the door
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5grl1boy
Rookie Author Ontario

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Message Posted: Oct 19, 2011 6:09:10 PM

I go by the door.
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Titanic1985
Champion Author South Carolina

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Message Posted: Oct 19, 2011 6:04:18 PM

Hello gvan. You and others are correct. Always go by the sticker on the driver side door post and ALWAYS inflate your tires when they are cold. I have an SUV with real time pressure readings. In the summer time in South Carolina when the temperature is 105 or higher I've seen an increase of pressure as much as 4 PSI. The sticker is specific for your vehicle. The tire pressure listed on the tire is its maximum safe inflation rate, not what you are to put in it. Consider the above senerio, if you put in the maximum tire pressure rating and it raises four PSI on a hot day, you are now exceeding the maximum and will eventually cause a blowout or ply separation. Gvan has done the homework - it is 99% accurate and indisputable.

An additional note is to go by the PSI on the door post. Owner's manuals are written before the vehicle goes into production and are subject to change. That is my 1% disagreement with gvan's report.

Something else to consider is what you are doing with the vehicle. Take a pickup truck for example. It is designed for Gross Vehicle Weight. It also carries a trailer tongue weight and a maximum towing weight. P rated tires (P means passenger) are not suitable for this application. If the vehicle being towed is heavy enough, you must go with a 6 ply tread and a 4 Ply sidewall. In this case, it is best to consult with tire experts to determine what is right inflation for your situation.

My thanks to gvan for doing the research. The only discrepancy I found was referring to the owner's manual which frequently doesn't address the tire issue. When you buy a new vehicle, oftentimes it comes with additional tire information since they don't always put the same brand of tire on every vehicle type (e.g. a Lincoln Continental Town Car came with Michellin tires while it's twin the Mercury Grande Marquis came with Firestone -- the same class / weight vehicle, but different tires.

Another issue is the donut spare tire. It IS to filled to the inflation written on the tire, but it is NOT to be driven beyond the speed limit on the sidewall. I see people going over 70 MPH with the donut tire. That is an accident waiting to happen for sure!



[Edited by: Titanic1985 at 10/19/2011 6:07:32 PM EST]
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dontuknowOH
Champion Author Ohio

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Message Posted: Oct 19, 2011 4:09:27 PM

I would like to add; Using a dial guage,if you hear air escaping while or at the time you pull the gusge away from the tire stem,that reading may be lower than the correct lbs. by a few. If this happens another try is necessary,there should be no air noise other than a slight air pop hiss sound to get a proper reading.

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gvan
Champion Author Chicago

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Message Posted: Oct 19, 2011 1:37:05 PM

Michelin website:

How to Check Tire Pressure
Tires have been known to lose up to 1psi (pounds per square inch) every month, so check all tires, including your spare, once a month (or before a long trip). It’s easy. Here’s how:

1.Purchase a trusted pressure gauge.
2.Check your tires “cold” – before you’ve driven or at least three hours after you’ve driven.
3.Insert pressure gauge into the valve stem on your tire. (The gauge will “pop” out and show a measured number. When you hear a “pssst” sound, that’s air escaping the tire. The escaping air shouldn’t affect pressure substantially, unless you hold down the air pressure gauge too long.)
4.Compare the measured psi to the psi found on the sticker inside the driver’s door of your vehicle or in owner’s manual. DO NOT compare to the psi on your tire’s sidewall.
5.If your psi is above the number, let air out until it matches. If below, add air (or have a Michelin retailer help you) until it reaches the proper number.
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