Hot versus Cold Tire Pressures?
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From: Schaumburg IL
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St. Jude Donor '06-'10, '13
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From: Horncastle Lincolnshire, England
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Correct me if I'm wrong but I would think Goodyear would probably be the one to work with GM in determining tire pressure. GM did not make the tires Goodyear did, or did I miss something?
30PSI cold is what the recommended pressure is on the stock tires on the C5, look on the tag on the door. If you are talking about aftermarket tires well then you need to check with the Manufacturer of that tire...or the tire shop where you got it to get the recommended running pressure. Most tires if you look on them will tell you what PSI not to exceed.
Running 35 PSI when it's hot out is about right. You will gain about 3-4 PSI going cold to hot. Stick with 30 PSI cold and you'll be fine..... unless you plan on running your car at Daytona at 200MPH for 500 miles.. then you might consider running Nitrogen rather than air
in all seriousness though if you really want to regulate the PSI and don't want to gain that much then like Mqn suggested get the tires inflated with Nitrogen.
30PSI cold is what the recommended pressure is on the stock tires on the C5, look on the tag on the door. If you are talking about aftermarket tires well then you need to check with the Manufacturer of that tire...or the tire shop where you got it to get the recommended running pressure. Most tires if you look on them will tell you what PSI not to exceed.
Running 35 PSI when it's hot out is about right. You will gain about 3-4 PSI going cold to hot. Stick with 30 PSI cold and you'll be fine..... unless you plan on running your car at Daytona at 200MPH for 500 miles.. then you might consider running Nitrogen rather than air
in all seriousness though if you really want to regulate the PSI and don't want to gain that much then like Mqn suggested get the tires inflated with Nitrogen.
OAT has always made the biggest difference to me
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Correct me if I'm wrong but I would think Goodyear would probably be the one to work with GM in determining tire pressure. GM did not make the tires Goodyear did, or did I miss something?
30PSI cold is what the recommended pressure is on the stock tires on the C5, look on the tag on the door. If you are talking about aftermarket tires well then you need to check with the Manufacturer of that tire...or the tire shop where you got it to get the recommended running pressure...
30PSI cold is what the recommended pressure is on the stock tires on the C5, look on the tag on the door. If you are talking about aftermarket tires well then you need to check with the Manufacturer of that tire...or the tire shop where you got it to get the recommended running pressure...
In short -- tire pressure has nothing to do with the tire manufacturer. It's the car.
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From: Horncastle Lincolnshire, England
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Burning Brakes
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From: Tacoma WA
People talking 1-2lbs difference hot cold must not be heating their tires up enough...
Mine jump from 29 in the mornings (when it's low 40's out in WA) to bout 34-35 Hot after a little while of driving (In the upper 50's outside)I'd tend to agree that any numbers between 25 and 40 are ok. Mix it up a little too, run a little lower in the back for More traction, and a little higher up front for better steering response.... Like 32 front 29 Rear, or something...
-Dan
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St. Jude Donor '06-'10, '13
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The tire pressure on the tire is max pressure for the tire, the tire pressure that is recommended for a car is by weight of the vehicle. It is a recommended cold pressure and the owner should check the pressure and tire wear once a month. You can adjust the pressure according to wear, center too much air, outside tread wear not enough air. You should start at the proper pressure recommended by the auto manufacture ( most times on the drivers door), not the pressure on the tire.
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From: Ocean Springs MS
"But it's used in airplane tires." N2 is used in aviation tires only because the lack of water vapor at very low temps keeps ice from forming. It is also used in brake accumulators, because it is inert and will not react with hydraulic fluid. As more evidence that N2 doesn't stay at a constant pressure, Nitrogen filled accumulators have a nominal pressure, usually at 70 deg F, on Boeing jets, with a correction in pressure for higher or lower temps
The only advantage N2 has over air is the lack of oxygen might lessen the oxidation of the inside of the tires, if the tires are on the car long enough for that to be a factor. Personally, my tires are worn out long before the rubber oxidizes.
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Burning Brakes
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From: Foresters Falls(near Ottawa) Ont
The door sticker 30 psi took the center out of my Michelin Pilots. I lowered the pressure to 28 psi cold, I guess the damage was done, the center of the tread was gone anyways. If anything, I might have got a bit more use out of the outside of the tread at 28 psi.
I have wondered if the Michelin, although the stock size, is too wide for the rim. Too narrow a rim for a given tire will take the center out regardless of the pressure!
My two cents!
RonJ ...
I have wondered if the Michelin, although the stock size, is too wide for the rim. Too narrow a rim for a given tire will take the center out regardless of the pressure!
My two cents!
RonJ ...
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Just ordered some air for the winter.Thanks!
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Frank -- see below.
The tire pressure on the tire is max pressure for the tire, the tire pressure that is recommended for a car is by weight of the vehicle. It is a recommended cold pressure and the owner should check the pressure and tire wear once a month. You can adjust the pressure according to wear, center too much air, outside tread wear not enough air. You should start at the proper pressure recommended by the auto manufacture ( most times on the drivers door), not the pressure on the tire.
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St. Jude Donor '06-'10, '13
Absolutley, I know there are other factors that come into play.. weight of car, ambient temp, contact patch...etc.. I was replying more to the statement that said " tire pressure has nothing to do with tire manufacturer" obviously the tire manufacturer makes the tire and knows it's limit and what range PSI it should be used at..depending on the other factors.The Vehicle manufacturer makes a recommendation based on the vehicle , that is safely within what the Tire manufacturer designed the tire for.
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Have been running 30# cold tire pressures. After extended Interstate driving periods the pressures will jump up to around 36#. (Driving in the eastern CA and western AZ recently.) This seems too high to me. Not enough miles to see any excessive center wear, but really don't want to. Question is, what is the optimum hot tire pressure recommendation for our cars? I don't think I have ever seen these numbers. I guess you would have to know some things: Goodyear runflats, interstate cruising, and about 70 degrees? Anybody have any experience?
Bill
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The door sticker 30 psi took the center out of my Michelin Pilots. I lowered the pressure to 28 psi cold, I guess the damage was done, the center of the tread was gone anyways. If anything, I might have got a bit more use out of the outside of the tread at 28 psi.
I have wondered if the Michelin, although the stock size, is too wide for the rim. Too narrow a rim for a given tire will take the center out regardless of the pressure!
My two cents!
RonJ ...
I have wondered if the Michelin, although the stock size, is too wide for the rim. Too narrow a rim for a given tire will take the center out regardless of the pressure!
My two cents!
RonJ ...
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In the spring and on into summer, starting off with 30# cold, in less than 10 miles of expressway speeds, the tires are up to 36 or more and will usually set off the "hi-pressure" alarm.
And in the fall, and on into winter, starting off with 30# cold, will frequently result in tire pressures under 25# in the morning, this time setting off the low pressure alarm.
That's how it was with the run craps and it certainly seems that is how it's going to be with the GY GS3D's as well. I've already had to bump up the 30# cold pressure a couple times to get the pressure back up to 30# and it's only in the 40's around here. It hasn't even GOTTEN cccccold yet.
There is no time of the year out here, where you can simply "set 'em and leave 'em". No lie, there is over 10# of difference in tire pressure between a 20° day and a 90° day here in the Midwest.
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Really now? Here in Iowa, in the spring, 30# cold is not the same as 30# cold in the fall....or the summer, or in winter.
In the spring and on into summer, starting off with 30# cold, in less than 10 miles of expressway speeds, the tires are up to 36 or more and will usually set off the "hi-pressure" alarm.
And in the fall, and on into winter, starting off with 30# cold, will frequently result in tire pressures under 25# in the morning, this time setting off the low pressure alarm.
That's how it was with the run craps and it certainly seems that is how it's going to be with the GY GS3D's as well. I've already had to bump up the 30# cold pressure a couple times to get the pressure back up to 30# and it's only in the 40's around here. It hasn't even GOTTEN cccccold yet.
There is no time of the year out here, where you can simply "set 'em and leave 'em". No lie, there is over 10# of difference in tire pressure between a 20° day and a 90° day here in the Midwest.
In the spring and on into summer, starting off with 30# cold, in less than 10 miles of expressway speeds, the tires are up to 36 or more and will usually set off the "hi-pressure" alarm.
And in the fall, and on into winter, starting off with 30# cold, will frequently result in tire pressures under 25# in the morning, this time setting off the low pressure alarm.
That's how it was with the run craps and it certainly seems that is how it's going to be with the GY GS3D's as well. I've already had to bump up the 30# cold pressure a couple times to get the pressure back up to 30# and it's only in the 40's around here. It hasn't even GOTTEN cccccold yet.
There is no time of the year out here, where you can simply "set 'em and leave 'em". No lie, there is over 10# of difference in tire pressure between a 20° day and a 90° day here in the Midwest.
If your tires are changing from 30 to 25, that means the temperature changed from 82 degrees that evening to 32 degrees the next morning.
Strange weather -- probably global warming.
Read about it here: http://www.tirerack.com/tires/tirete....jsp?techid=73
On the other side, I have never seen the pressures go from 30 lbs. to 36 lbs. in ten miles of highway driving. Your results vary.