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Old 12-19-2008, 07:57 PM   #1
iyzmi
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Default Tire Pressure in Winter

Just wondering what you guys think the best tire pressure for winter is. I'm want the best snow/ice grib out of my tires without sacrificing too much fuel economy. I had my tires at about 30psi in the summer but I think 25psi would be better for the winter...

BTW, I'm on Potenza RE960AS tires if that makes any difference.
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Old 12-20-2008, 10:24 AM   #2
Nomadgene
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Copied directly from Tirerack.com's winter tire tech link.


"Several vehicle manufacturer's owner's manuals recommend operating winter tires several psi (typically 3-5) higher than their recommended pressures for summer and all-season tires. While none of them actually provide the reason why, there are several scenarios that would support the practice.

First and foremost is that winter tires feature more aggressive tread designs, softer tread compounds and are often molded with deeper beginning tread depths than summer or all-season tires. While the combination of these design elements allows winter tires to remain more pliable in sub-freezing temperatures to provide more traction in snow and on ice, it often results in tires that have somewhat reduced responsiveness to driver input. The 3-5 psi higher recommended inflation pressures increase tire stability and help offset the reduction in responsiveness.

Additionally ambient air temperatures in winter typically range 40- to 50-degrees Fahrenheit colder than typical summer temperatures for the same location. The lower ambient temperatures allow tires to be more efficient at radiating heat and the tires will run cooler, building up less hot tire pressure. In this case, the 3-5 psi higher recommended inflation pressure increase helps offset the reduced hot tire pressures resulting from less heat buildup.

And finally, all tire pressures are intended to be measured cold, which means when the tires are at the same temperature as the air outside. Unfortunately, unless you park your vehicle outside or in an unheated, detached garage, and measure its tire pressures first thing on dark, cold mornings, the influence of attached garages or higher ambient air temperatures later in the day often means that drivers are actually measuring tires that are not completely cold. In this case the 3-5 psi higher recommended inflation pressure increase helps offset the reduced tire pressures associated with the conditions in which the tire pressures are typically measured.

You may also want to read "Air Pressure: When and How to Set" "
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Old 12-20-2008, 12:04 PM   #3
iyzmi
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Ok, that quote is completely useless for me because:
a. I don't have winter tires.
b. I'm not operating my non-existing winter tires in the summer.

I'm pretty sure raising the PSI 3-5 higher from what I usually run will give me LESS traction. Thanks anyway.
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Old 12-20-2008, 03:26 PM   #4
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Quote:
Originally Posted by iyzmi View Post
Just wondering what you guys think the best tire pressure for winter is. I'm want the best snow/ice grib out of my tires without sacrificing too much fuel economy. I had my tires at about 30psi in the summer but I think 25psi would be better for the winter...

BTW, I'm on Potenza RE960AS tires if that makes any difference.
Quote:
Originally Posted by iyzmi View Post
Ok, that quote is completely useless for me because:
a. I don't have winter tires.
b. I'm not operating my non-existing winter tires in the summer.

I'm pretty sure raising the PSI 3-5 higher from what I usually run will give me LESS traction. Thanks anyway.

However, your line of thinking looks to be going completely opposite of the information provided above. Instead of INCREASING tire pressure, you are trying to DECREASE tire pressure.

Basically there seems to be at least 2 good reasons leading to INCREASING tire temperatures in colder climates.

1) Because the ambient air is much colder, the tires will not heat up to the same degree as normal, nor will they heat up as quickly. To counteract that, you should increase the amount of air in the tire.

2) If you are traveling on a trip in the snow or colder climates, usually that means there is more weight in the vehicle (i.e. extra people, extra luggage, etc.). You would need to INCREASE the tire pressure to be able to hold the additional weight safely in your vehicle.

You probably want to try adjusting your tire temperatures until you find what works, but I probably would not advise DECREASING the tire pressure in the colder climate vs what you normally run in a warmer (Summer) climate.
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Old 12-20-2008, 04:15 PM   #5
iyzmi
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I'm just gonna inflate them back up to factory spec and be done with it. I think that would be best.
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Old 12-20-2008, 07:02 PM   #6
EdHilario
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lol okay? People tried to help but you just ignore it. You should actually raise the tire pressure above factory spec by about 4 PSI (roughly 36 or so). Other than that, getting winter tires would be the next best thing.

By the way, people increase fuel economy by raising their PSI which in turn is a bit of sacrifice on handling characteristics.
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Old 12-20-2008, 07:06 PM   #7
iyzmi
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I've checked on google and found that most people say to keep the tire pressure at the factory spec for all-season tires in the winter. I also found that for winter tires, it is recommended to go 2-4psi higher than usual. Since I do not have winter tires, what people have recommended above does not apply in my case and I'll stick with what the majority think about tire pressure specifically for all-season tires.

lol, I just re-read that and it sounded so repetitive.
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Old 12-20-2008, 08:34 PM   #8
EdHilario
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Well try bumping up the PSI though and religiously check it because of the temperatures. Safe driving to you.
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Old 12-20-2008, 08:46 PM   #9
iyzmi
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Will do. Thanks!
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Old 12-20-2008, 09:12 PM   #10
yeos
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My RE960AS's seem a bit more squirrely at 35f/32r. Before, they were at the 31/29. I'm gonna try out 34/31 tomorrow if I decide to go out. My tires have just under 1k miles on them btw.
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Old 12-20-2008, 09:37 PM   #11
iyzmi
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LMK how 34/31 works out for you.
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Old 12-22-2008, 09:59 PM   #12
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Well I drove this morning 35 miles on a freeway covered in ice and snow. Car felt like wandering more than usual, but I don't expect these uhpas to handle like a winter tire. Very easy to point the wheel, hit the gas, and go in the direction I want to go. I'm going down to 32/30 after christmas when I go back to work.
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