Tire pressure. How much is too much or too little?

You’re tires will say (around the wheel) how much pressure they need.

@justn I’ve never seen a tire that says the pressure for the right application. They usually just say the max you can put in the tire, which is not recommended and I certainly wouldn’t put that 44psi as listed on my tires in there.

Your owner’s manual or the sticker inside the driver door will tell you what the cold (i.e. before you go driving) inflate pressure should be. Mine, for example, is 29 psi.

If you don’t use factory recommended tires, then idk.

I honestly don’t remember what the recommended PSI is for the tires on my car… but a few years ago was surprised to find that while most car tires will require around 34 psi… the tires on my road bike require 120psi. weird no?

@Dr_C Not that weird, because psi is a measure of pressure per square inch and not volume of air in a given space. My bike tires take a lot of pressure as well as my Yukon XL which requires 85psi (what we run it at when we’re towing with it)

@kevbo yea, I understand the “cold” thing. I’m no n00b to cars, lol. Although, I did forget about the door jam. I’m gonna check that out right now….. Under futher inspection of the door jam it wasn’t listed. Luckily I do have the owners manual and it said, “cold inflation is required to see the correct psi check the gas tank flap door.” It wasn’t there, lol.

In that case:

“European or African Golf?”

@kevbo Mexican! lol, the car was actually built in Mexico unfortunately, but it’s for American use, so european? lol I’m not sure.

Go by the car manufacturer’s recommended tire pressure. The cars chassis was designed around it.

The figure on the tire’s sidewall is the maximum safe pressure according to the tire manuacturer, not nearly as specific to your application as the car manufacturer’s suggestion.

Typically higher pressures improve fuel economy (lower rolling resistance) and better cornering (increased slip angle).

@Noel_S_Leitmotiv I know this, lol. I just am not sure where to find the manufacturer’s recommendation. It’s not listed in the owner’s manual or where it says it’s supposed to be listed. When I first got the car the pressure was low and I was getting 23mpg in city and when I asked my roommate (at the time) he searched on some website and it had suggested pressures that I tried until I got these new tires. On the old tires I got 27mpg and close to 33mpg on the freeway, but I want to know a happy medium for most correct according to manufacturer Fuel consumption and cornering. I like to corner, but I like to save money too, lol.

Try the car’s doorjamb, glovebox or center console box door, or sunvisors.

@Noel_S_Leitmotiv “Although, I did forget about the door jam. I’m gonna check that out right now….. Under futher inspection of the door jam it wasn’t listed. Luckily I do have the owners manual and it said, “cold inflation is required to see the correct psi check the gas tank flap door.” It wasn’t there, lol.” in a previous response.

There’s no glovebox, I know it’s very strange, lol. I could check the center tiny box and the sunvisors, but it’s looking slim, lol….. and that’s a nope and nope. I also checked the stickers under the hood and that’s also a no go.

If your tires seem like rocks when going over bumps, try lowering the pressue. Best bet is to lookup the tire on the manufacturer website and go from there.

The correct tire pressure for the tires on your car is the pressure listed in the owners manual or on the door sticker. I would also suggest thet when replacing the tires on your car you should purchase the same brand and type of tire the vehicle came with from the factory. I work for an Amreican auto company in Chassis Controls (ABS, Traction Control and Stability Control systems) These systems are developed,calibrated tested and validated using the tires the vehicle is sold with. If the tires are changed or if the tire PRESSURE is changed during the development process the system is revalidated to make sure it still functions as designed. The same is true if you are thinking about installing larger rims. Bigger rims are much heaver than smaller ones and can affect the performance of these important safety systems. IMHO

@csimme01 I don’t think this has SC or TC & I know it doesn’t have ABS. Also the tire “pressure” is not listed in the manual, door jam, sun visor, gas tank lid (where it says it should be via the owners manual), or under the hood. Thank for the info though, even if I already knew it. :)

@Axemusica Yes, I read the rest of your answers and I see your problem. I didn’t find any info for those tires on the web. I have some resources at work that may have the info. BTW the number on the sidewall of the tire is the pressure for the maximum load capacity of the tire. It is in no way related to the use on a specific vehicle. Some people use this number because they feel it will give better fuel economy. The problem is, as you stated, it affects handling. It can also afffect stopping distance (with or without ABS), high speed stability and the vehicles roll over performance. I will get back to you if I can find the numbers for you.

@csimme01 sweet thnx. I was gonna try the chalk thing when I got around to it, but I couldn’t find the right chalk & it’s becoming winter here. Raining & snowing & blahhh.

@Axemusica Well I tired.. I checked Mitchell 1 on demand and all it says about tire pressure is “See Sticker On Vehicle” Have you call a dealer?
Sorry I couldn’t be of more help.

I always go by whatever pressure allows me to get even wear across the width of the tire, so long as it doesn’t exceed the maximum PSI of the sidewall.

For most cars I’ve had, even maximum pressure in the front tires leads to excessive wear on both edges while leaving the center nearly untouched (a traditional sign of underinflation) though the rear often does better at 4–6PSI below what the fronts run. And, of course, I have had a couple of cars where that wasn’t true soyou need to do a little trial-and-error.

The pressures I use are still above what the doorjamb recommends, but bear in mind that that recommendation is for a particular brand/size/style of tire so it will be wrong if you use any other tires. It will also be wrong if you don’t drive exactly like they did when arriving at that number, and I tend to drive a little more aggressively than a grandmother. Driving at speeds >15MPH puts a little more force on the tires than the wusses who were seeking the best ride quality, so I pretty much have to put in at least 2PSI more than factory specs just to account for that.

Higher pressure generally increases your MPG, but as for performance… it depends. You have less rolling resistance, but also usually wind up with a smaller contact patch, so overall traction may be reduced. I say “may” since that depends on the stiffness of the tire, the pressure, and the suspension geometry of the vehicle. Personally, I find that going a little over makes my cars more predictable since the tread doesn’t wiggle as much in relation to the rim as it would if I ran at stock pressures, but it is possible to overdo, hence part of the reason why I generally run so much lower pressure in the rear tires.