18" Summers to 17" winters, what to set tire pressures

[kenghk]

I looked everywhere for an answer but couldn't find one. 225/40/18 at 35psi front and 34psi back in the summertime and 215/50/17 for winters. What do you set the pressures at on the 17s? The tireshop said just put 32psi in it. Stock Mazda3 with 17s say 32psi.....they're 205s?

Any ideas?

[aris]

Set it at what your door says

[cwp_sedan]

You don't set the air pressure by the time of wheel or tire. It's determined by the manufacturer what the optimal pressure is for safety and fuel economy.

Like Aris said, check your drivers door frame. It will say there.

[kenghk]

It says 35/34 front to rear for 18s and that's it, no other sizes listed.

What do you make of the regular 3 having different tire pressures for the 15", 16" and 17" models? If you had a GT and the 17" ask for 32psi and then you went to 16" snows wouldn't you set them to 35psi like it says to do for the 16s?

[dietsprite]

The door label says it should be 36psi however after my first scheduled maintenance, the dealership put 32psi into it so im confused which pressure measure is the optimal one

[kenghk]

The door label says it should be 36psi however after my first scheduled maintenance, the dealership put 32psi into it so im confused which pressure measure is the optimal one

I assume you have 15s. As far as I know the 17's need 32psi, the 16's need 35psi and the 15's need 36psi so the tech biffed.

[dietsprite]

I assume you have 15s. As far as I know the 17's need 32psi, the 16's need 35psi and the 15's need 36psi so the tech biffed.

My stock wheels are 205 55 16"

[rzapata]

People, you've got it all confused. Aris and cwp_sedan had already clarified the answers for you. All this speculating will just confuse other readers.

Go by whatever the door sticker says. That's your "optimal" pressure, maybe +- a few PSI (or something). The tires aren't gonna blow if you add a few pounds of air in it.

[Booter22]

do you have a speed 3? which would be why it doesnt say a size for 16/17 as it wouldnt come from the factory with them, same way my gs wont have 18" as it wont come with them but for 17s should be - but if you flip to your owners manual which is always a good place to check first.. section 10 page 9 -

205/55R16 - 35 PSI Front and Rear
205/50R17 - 32 PSI Front and Rear
225/40R18 - 35 PSI Front And 34 PSI Rear

So best bet. 32 PSI front and rear. if well the weather is warmer(+'S) you could go 34 or so im sure, and as it gets colder. 32. just make sure to not inflate past the tires max. should be on the side wall.

[kenghk]

I looked everywhere for an answer but couldn't find one. 225/40/18 at 35psi front and 34psi back in the summertime and 215/50/17 for winters. What do you set the pressures at on the 17s? The tireshop said just put 32psi in it. Stock Mazda3 with 17s say 32psi.....they're 205s?

Any ideas?

the 215/17 and 225/18 have nearly the same volume so i can see going with what's on the door. If i had 205's I'd go with 32psi....I've been thinking about this for a while.

[alexo]

You don't set the air pressure by the type of wheel or tire. It's determined by the manufacturer what the optimal pressure is for safety and fuel economy.

Not necessarily. For an alternative view, by somebody who presumably knows what he's talking about see here (http://www.carbibles.com/tyre_bible_pg3.html#correctpressure).

[Zuluwun]

Not necessarily. For an alternative view, by somebody who presumably knows what he's talking about see here (http://www.carbibles.com/tyre_bible_pg3.html#correctpressure).

That was actually a pretty good read.

[alexo]

Glad to help :)
I'm actually just learning about it so I share my findings for others to consider.

[Booter22]

the 215/17 and 225/18 have nearly the same volume so i can see going with what's on the door. If i had 205's I'd go with 32psi....I've been thinking about this for a while.

.. but 32 psi in a 215/17 and 32 psi in a 225/18.. will still be 32psi.. so if you had 205s at 32psi it would still be 32psi.. it would technically take less/more "air" to actually get you to 32psi depending on the tire size.. but at the end of the day 32 psi is 32 psi.. and perfect for winters. i find more then that is good for fuel economy but the traction goes down. on days with more snow. 30 psi if good too. but to each there own...


.....32psi.... :chuckle had to say it again sorry.

[segato13]

The Door plaque sticker or your manual recommendations. Don't over or underinflate your tires

[silverstarmazda]

i would say inflate according to the tire. (5-10 psi lower than max). door frame sticker is for the tire size that came with the car. if you got tires (summer or winter) with a different size than what came with the car. sometimes the tire will require less or more air pressure.

for example. the tires i have on my car now are 225/45/17 kumho asx that i put 45 psi. max psi is 50. i run a higher psi for fuel economy purposes. if i follow what the door says, my tires would pretty much be flat (tried that).

i said in another thread a while ago i change my winter tire air pressure according to what i see on the forecast.

[Booter22]

Exactly. i have my summer psi around 38-40, and winter i keep around 30-34, if theres no snow. more towards 34 ish. if snow. around 30. higher = fuel econ. lower = traction. in between = balance of both.

[rzapata]

i would say inflate according to the tire. (5-10 psi lower than max). door frame sticker is for the tire size that came with the car. if you got tires (summer or winter) with a different size than what came with the car. sometimes the tire will require less or more air pressure.

for example. the tires i have on my car now are 225/45/17 kumho asx that i put 45 psi. max psi is 50. i run a higher psi for fuel economy purposes. if i follow what the door says, my tires would pretty much be flat (tried that).

i said in another thread a while ago i change my winter tire air pressure according to what i see on the forecast.

You do realize that at bumps and uneven road surfaces, relative pressure in the tire rises right? Bringing it closer to max will increase your chance of tire failure. But hey, if that works well then disregard my statement. :)

[silverstarmazda]

You do realize that at bumps and uneven road surfaces, relative pressure in the tire rises right? Bringing it closer to max will increase your chance of tire failure. But hey, if that works well then disregard my statement. :)

thats absolutely right. but the shocks absorb some of the bumps. and much like driving a lowered car you should always look at the road. the tire can withstand more psi above max pressure actually. some eco nuts inflate past the max mark. and unless its a crazy pot hole, your tires should be ale to handle it while under max psi.

[midnightfxgt]

i would say inflate according to the tire. (5-10 psi lower than max). door frame sticker is for the tire size that came with the car. if you got tires (summer or winter) with a different size than what came with the car. sometimes the tire will require less or more air pressure.

for example. the tires i have on my car now are 225/45/17 kumho asx that i put 45 psi. max psi is 50. i run a higher psi for fuel economy purposes. if i follow what the door says, my tires would pretty much be flat (tried that).

i said in another thread a while ago i change my winter tire air pressure according to what i see on the forecast.

Please dont listen to this. Running your tires at 45PSI will also decrease the longevity of the tire.

Always fill to your door card pressure, plus of minus a few PSI for preference.

-John

[silverstarmazda]

Please dont listen to this. Running your tires at 45PSI will also decrease the longevity of the tire.

Always fill to your door card pressure, plus of minus a few PSI for preference.

-John

i never said you had to inflate to 45 psi. i said 'I" inflate them to 45 because thats wat my tires call for. i said to inflate them to what your tire says (5-10psi lower from max). tires come in all sizes, designs, and manufacturing process which may require a different air pressure than what is stated on the door. please do not tell someone they are wrong. when you are not completely right yourself. people do things differently and there is more than one way to be right

[aris]

i never said you had to inflate to 45 psi. i said 'I" inflate them to 45 because thats wat my tires call for. i said to inflate them to what your tire says (5-10psi lower from max). tires come in all sizes, designs, and manufacturing process which may require a different air pressure than what is stated on the door. please do not tell someone they are wrong. when you are not completely right yourself. people do things differently and there is more than one way to be right

Hate to burst your bubble but he used to own a tire shop and he knows what he's talking about...you on the other hand don't know what your talking about :p

[aris]

i never said you had to inflate to 45 psi. i said 'I" inflate them to 45 because thats wat my tires call for. i said to inflate them to what your tire says (5-10psi lower from max). tires come in all sizes, designs, and manufacturing process which may require a different air pressure than what is stated on the door. please do not tell someone they are wrong. when you are not completely right yourself. people do things differently and there is more than one way to be right


i would say inflate according to the tire. (5-10 psi lower than max). door frame sticker is for the tire size that came with the car. if you got tires (summer or winter) with a different size than what came with the car. sometimes the tire will require less or more air pressure.


Omg you yes you did say it

[midnightfxgt]

i never said you had to inflate to 45 psi. i said 'I" inflate them to 45 because thats wat my tires call for.

No your tires do NOT. You are wrong. The Maximum pressure does NOT affect how much air you should fill them with!


i said to inflate them to what your tire says (5-10psi lower from max). tires come in all sizes, designs, and manufacturing process which may require a different air pressure than what is stated on the door.

Wrong. Again, MAX pressure is no indication of what you should run them at.



please do not tell someone they are wrong. when you are not completely right yourself. people do things differently and there is more than one way to be right

If your wrong, and it could affect someone else, of course, I should tell you, and them!

I am right. Having sold all of the major brands of tires, and installed them on thousands of cars, I would hope I know a thing or two about what I am talking about. There is not more than one way to be right here. The MAX pressure listed on a tire does not play a factor in what the OP should inflate his tires to, plain and simple.

-John

[Booter22]

.. but 32 psi in a 215/17 and 32 psi in a 225/18.. will still be 32psi.. so if you had 205s at 32psi it would still be 32psi.. it would technically take less/more "air" to actually get you to 32psi depending on the tire size.. but at the end of the day 32 psi is 32 psi.. and perfect for winters. i find more then that is good for fuel economy but the traction goes down. on days with more snow. 30 psi if good too. but to each there own...


.....32psi.... :chuckle had to say it again sorry.

anyway.... still think 32 PSI is your best call for your winters. 34 psi if you want but cant go wrong with 32PSI in winter.

[silverstarmazda]

Hate to burst your bubble but he used to own a tire shop and he knows what he's talking about...you on the other hand don't know what your talking about :p

oh jeez... im not even bother fighting you. u obviously just go against me because you dont like me. even though ive put real world info out there. you seem to go by paper rather than reality

[peterm15]

http://www.goodyear.eu/ie_en/tire-advice/faq/air-loss.jsp


. How much air should I put in my tires?


Proper inflation is the single most important part of tire care. The inflation pressure on the side of the tire is the MAXIMUM operating pressure. It is not necessarily the right inflation for your vehicle. Always use the inflation recommended by the vehicle manufacturer. You can find it in your owner's manual, posted on the edge of the driver's door, on a door post or on the inside of the glove box door. Always check inflation when tires are COLD: when the vehicle has been driven less than a mile or one hour or more after driving. Use a good quality tire gauge. Note: It's natural for radial tires to have a slight bulge in the sidewall at their proper inflation pressure. Check or adjust inflation every few weeks, before any long trip or if travelling with a heavy load. And don't forget to check the spare. Your Goodyear retailer can answer any questions you may have about tire inflation.

[Booter22]

How much air should I put in my tires?


Proper inflation is the single most important part of tire care. The inflation pressure on the side of the tire is the MAXIMUM operating pressure. It is not necessarily the right inflation for your vehicle. Always use the inflation recommended by the vehicle manufacturer. You can find it in your owner's manual, posted on the edge of the driver's door, on a door post or on the inside of the glove box door. Always check inflation when tires are COLD: when the vehicle has been driven less than a mile or one hour or more after driving. Use a good quality tire gauge. Note: It's natural for radial tires to have a slight bulge in the sidewall at their proper inflation pressure. Check or adjust inflation every few weeks, before any long trip or if travelling with a heavy load. And don't forget to check the spare. Your Goodyear retailer can answer any questions you may have about tire inflation.

http://www.goodyear.eu/ie_en/tire-advice/faq/air-loss.jsp

..!

205/55R16 - 35 PSI Front and Rear
205/50R17 - 32 PSI Front and Rear
225/40R18 - 35 PSI Front And 34 PSI Rear

Dare i say more? 32 PSI! :super smiley

[aris]

oh jeez... im not even bother fighting you. u obviously just go against me because you dont like me. even though ive put real world info out there. you seem to go by paper rather than reality

lol real word info? really

[silverstarmazda]

No your tires do NOT. You are wrong. The Maximum pressure does NOT affect how much air you should fill them with!



Wrong. Again, MAX pressure is no indication of what you should run them at.




If your wrong, and it could affect someone else, of course, I should tell you, and them!

I am right. Having sold all of the major brands of tires, and installed them on thousands of cars, I would hope I know a thing or two about what I am talking about. There is not more than one way to be right here. The MAX pressure listed on a tire does not play a factor in what the OP should inflate his tires to, plain and simple.

-John


MY tires call for 50 max, if i inflated to door specs they will be flat. following you door card specs to some tires will have u running under pressure. the max pressure is set so you dont over inflate them. ive worked at multiple dealerships and shops and have installed thousands of oem and aftermarket tires and wheels myself. your not the only one who works on cars here btw. ive never had a complaint as long as iver worked in any of them. you want mushie tires, fine. if you got something thats not oem (which is a majority of what we use) then you gonna have to change from oem spec a little bit. our competitor shop across the street to us followed the oem door card psi and nearly killed a guy because they didnt recognize that the tire was far under inflated for the tire and wheel design.

[silverstarmazda]

lol real word info? really

yes real world, you should be here sometime

[midnightfxgt]

oh jeez... im not even bother fighting you. u obviously just go against me because you dont like me. even though ive put real world info out there. you seem to go by paper rather than reality


He is probably against you, as your wrong. Still don't believe me? Lets see what some of the biggest names in tires say:

Goodyear: http://www.goodyear.eu/home_en/tire-advice/faq/tire-inflation.jsp

"The inflation pressure on the side of the tire is the MAXIMUM operating pressure. It is not necessarily the right inflation for your vehicle. Always use the inflation recommended by the vehicle manufacturer."

TireRack: http://www.tirerack.com/tires/tiretech/techpage.jsp?techid=8

"The "right" inflation pressures are those provided by the vehicle manufacturer, not the "maximum" inflation pressure branded on the tire's sidewall."

Michelin: http://www.michelinman.com/tires-101/tire-care/tire-maintenance/how-to-check-pressure.page

"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. "

Yokohama: http://green.autoblog.com/2008/04/23/yokohama-reminds-you-to-check-your-tire-pressure-regularly/

"The correct PSI (pounds per square inch of air pressure) that's right for tires is located on the vehicle's tire information label - not the sidewall of the tire."


There you have it. Just because you run your tires incorrectly does not mean that is how others should.

[midnightfxgt]

MY tires call for 50 max, if i inflated to door specs they will be flat. following you door card specs to some tires will have u running under pressure. the max pressure is set so you dont over inflate them. ive worked at multiple dealerships and shops and have installed thousands of oem and aftermarket tires and wheels myself. your not the only one who works on cars here btw. ive never had a complaint as long as iver worked in any of them. you want mushie tires, fine. if you got something thats not oem (which is a majority of what we use) then you gonna have to change from oem spec a little bit. our competitor shop across the street to us followed the oem door card psi and nearly killed a guy because they didnt recognize that the tire was far under inflated for the tire and wheel design.

Then you have a defect. at 32PSI, the tire will NOT be flat. Again.. you are wrong. Provide some proof to your claims, as I have above. All your doing is saying "I have done it, it is right".

Manufacturers, who know more than both of us combined should know the right way.

[silverstarmazda]

the only time i use the door card is when im either using oem sizes. or to use it as a low end number. i will inflate between the door spec and the tire max. i allow the air to heat up in the tire.

hey, do what you do and ill do what i do. im done with this crap on this forum. im not saying your wrong. not at all. i dont see why this has to blow up into a full out argument. you want to say im wrong? go ahead. ive been in the trade since ive entered high school and this has been my life.
http://autorepair.about.com/b/2009/12/08/more-debate-over-tire-pressure.htm
http://www.professionalfleet.com/lansing_auto_repair_articles/how_much_air_should_i_put_in_my_tires_what_air_pre ssure_should_i_use

i like a firmer ride and better cornering with the benifit of a longer lasting tire.
tire companies as the ones you listed obviously say to inflate to oem spec as they supply the tires for manufacturers for warranty purposes.

there has been debate over this topic MANY MANY times and not just for our cars. but tires in general

[midnightfxgt]

I will say your wrong, when your wrong. Continually doing something incorrectly doesnt make you right.

Again, if the manufacturers recommend it, perhaps you should listen. You have no other supporting evidence.

[Booter22]

the only time i use the door card is when im either using oem sizes. or to use it as a low end number. i will inflate between the door spec and the tire max. i allow the air to heat up in the tire.

i like a firmer ride and better cornering with the benifit of a longer lasting tire.

just a quick note. yes i agree with the firmer ride, i find when your not going straight the tires are " less" effective as they dont grip as well with the higher pressure as it would stick with the lower. but you do find better fuel economy. however with either higher then normal or lower then normal tire pressure can cause the tires to wear out un even and premature. too high i beleive gets the inside of the tire and too low will do the outside edges and both can feather the tread if not correct as well. tire pressure being recommended from the factory based on different things, vehicle speed. weight, so on. and what the tire can / should be able to handle. now some tires being better / worse then the factory supplied tires. of course the door sticker being the best guide to go by. being a driver you can adjust the pressure to what you are comfortable with but of course shouldnt go too high above whats recommended or too low below it either, but when in doubt always fall to the recommended manufacture pressure.

at last thats how i do my tires. like i said higer in the summer for better fuel econ. 30-32 higest 34 for winter. and if i had a speed 3 some where around 36-38 as i do lots of high way and if i wanted to take it to the track or for some nice back roads driving down to 34 for some nice traction.

[midnightfxgt]

http://autorepair.about.com/b/2009/12/08/more-debate-over-tire-pressure.htm
http://www.professionalfleet.com/lansing_auto_repair_articles/how_much_air_should_i_put_in_my_tires_what_air_pre ssure_should_i_use


Neither of these is a good article with ANY supporting proof. Hell, the fleet company has so many spelling and grammatical errors, I could not take them seriously LOL.

[peterm15]

i allow the air to heat up in the tire.
What pressure is your tire set to when cold?

[silverstarmazda]

I will say your wrong, when your wrong. Continually doing something incorrectly doesnt make you right.

Again, if the manufacturers recommend it, perhaps you should listen. You have no other supporting evidence.

you have no authority to say anything about me as much as im saying about you. doing something over and over with a proven history and record make what im saying valid. but not suited to everyone.

manufacturers recommend it, but isnt mandatory. people have proven going out of "recommended" range have had pros with little cons. i have no other supporting evidence because its not just me, its a whole plethora of automotive enthusiasts out there who have explored this field.

[silverstarmazda]

What pressure is your tire set to when cold?

around 40 and after and auo-x session it raises up to about 45-46 and thats about it...

[peterm15]

around 40 and after and auo-x session it raises up to about 45-46 and thats about it...

Thanks.
Was just curious.

[midnightfxgt]

you have no authority to say anything about me as much as im saying about you. doing something over and over with a proven history and record make what im saying valid. but not suited to everyone.

manufacturers recommend it, but isnt mandatory. people have proven going out of "recommended" range have had pros with little cons. i have no other supporting evidence because its not just me, its a whole plethora of automotive enthusiasts out there who have explored this field.

Right. Just because people have done it, and have been successful, doesn't mean its right. I saw many many cars come in with over inflation wear (middle of the tire).

Setting tires based on tire AND auto manufacturer ratings is the RECOMMENDED way. For the average consumer (ie. the majority of this forum) this is the best way.

-John

[silverstarmazda]

Neither of these is a good article with ANY supporting proof. Hell, the fleet company has so many spelling and grammatical errors, I could not take them seriously LOL.

then you should search for real people on other forums for what they say they run. most of them dont follow the door spec for reasons. you owned a tire shop, you should know this by now. but i guess inflating tire pressures to oem spec will protect your business from warranty claims.

[silverstarmazda]

Right. Just because people have done it, and have been successful, doesn't mean its right. I saw many many cars come in with over inflation wear (middle of the tire).

Setting tires based on tire AND auto manufacturer ratings is the RECOMMENDED way. For the average consumer (ie. the majority of this forum) this is the best way.

-John

yes that is right. but we have people here who also run on aftermarket set ups. winter set ups are rarely the same specs as oem summers. yes it is the safest way, for warranty purposes and tire safety. but for some people, this isnt enough for performance.

[midnightfxgt]

Yes. Also, should a tire blow out and cause bodily harm, there is the whole pesky negligence law suit that could follow for not following the proper way of doing things by going against Tire and Auto manufacturer recommendations.

Its like using 91 Gas. Some will claim their car runs much better on it, or that it cleans the car out, or that they have added it once every 2 weeks, and their cars last forever. Lots do it. Doesnt make it the best thing.

Searching for people doing it doesn't make it right. Auto and Tire manufacturers spend boatloads of cash testing all of this. But hey, some guy on the net is a better indication! Fact is, there are MANY more people running OEM recommended specs.

Do what you want. You only have personal experience banking on this. I'd prefer to recommend based on FACTUAL information, from credible sources :)

[aris]

yes real world, you should be here sometime

Lol...

[Olestra]

for example. the tires i have on my car now are 225/45/17 kumho asx that i put 45 psi. max psi is 50. i run a higher psi for fuel economy purposes. if i follow what the door says, my tires would pretty much be flat (tried that).

Sorry have to chime in here because of all the misinformation.
This comment alone shows you don't have a clue about physics and should not be commenting on the matter at all.

Pressure is not a measurement that indicates how much air your tire has.
It's a measurement of force being applied to an area. In this case the area is your tire.
32 psi is 32 psi regardless of the tire. How can the tire be flat at 32 psi. It makes no sense.
The weight and weight distribution of the vehicle does not change so why would the pressure change.
As you can see from the manual, the pressure does change based on +/- sizing of the tire diameter.

Some tire manufacturers have vehicle specific pressures for a specific tire size. You can consult that as a trusted source.

Otherwise what you're doing is purely guessing.
Unless you have a scientific way of showing what the tire looks like at a certain pressure to determine the maximum contact patch then you're better off with the door placard's pressure.
Anything else I would argue is dangerous and at your own risk.

[loki]

you have no authority to say anything about me as much as im saying about you. doing something over and over with a proven history and record make what im saying valid. but not suited to everyone.

manufacturers recommend it, but isnt mandatory. people have proven going out of "recommended" range have had pros with little cons. i have no other supporting evidence because its not just me, its a whole plethora of automotive enthusiasts out there who have explored this field.

just stop talking. just stop. stop.

thanks.

If you continue to clutter this post up with shit, when you have one of the former owners of one of TM3's tire sponsors trying to teach you something.

then just stop.

again thanks.


If not Aitch has a hamster that he'd be willing to let you meet.

[Aitch]

yes that is right. but we have people here who also run on aftermarket set ups. winter set ups are rarely the same specs as oem summers. yes it is the safest way, for warranty purposes and tire safety. but for some people, this isnt enough for performance.

Let's quote this for posterity. After so many argumentative posts it seems you agree with John that the SAFEST way is to follow manufacturer specs. So obviously inflating to just under the max pressure (10-15psi over the normal range) isn't recommended for most drivers.

[/end thread]