Winter/summer tire pressure

Have enough trouble in sand with my skinny bike tires. The wider tires are certainly an improvement in adverse conditions.

I’ve read about people who drive on sand lowering tire pressure to grip better. I’d think the same would apply to snow. Snow on roads turns to ice quickly.

I’ve bicycled in snow on inch-wide 100psi tires. I got little traction; I couldn’t brake or turn. There are huge tires, like 4 inches wide, that people use on sand. I imagine they’d work better on snow too. I think they inflate to 40 psi.

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I’m a bit curious about the “off road” tires. Did she get “P” tires or “LT” tires. It will be at the beginning of the tire size, for example P225/70-16 or LT225/70-16.

If they are P tires, they will also have “load range B” on the sidewall. If LT, then the sidewall will be “load range D” or “load range E”.

If they are LT tires, then she needs to run about 15 psi over the recommended pressure on the placard located on the drivers side B pillar (door post).

Ah … Mmmmmm … Not exactly.

P type tires come in Standard Load (SL) and Extra Load (XL)

LT tires come in Load Ranges (LR) and a LR B would be an LT tire of some sort (There are different kinds!)

[quote=“keith, post:23, topic:180877”] , If they are LT tires, then she needs to run about 15 psi over the recommended pressure on the placard located on the drivers side B pillar (door post).
[/quote]

The 15 psi for LT tires over P type tires is correct and the tire pressure on the B pillar is mostly correct. The 2008 regulations state the vehicle tire placard has to be in the driver’s door frame area - and most vehicle manufacturers use the B pillar or the adjacent door sill. Prior to 2008, the placard location was not specified and could be found on any door post, or door (although the B pillar was common.) or in the glove box, or on the fuel filler door, or on the trunk lid.

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Now regarding the winter/summer pressure thing:

The stock answer is that there is no difference between the inflation pressure specified for winter and summer.

HOWEVER, it is common in winter for people to overinflate their tires a bit in order to cut through the snow to get down to the pavement, which has way, way more grip than snow does. The problem is that you can get better snow traction (not touching pavement!) by reducing the inflation pressure (just as people do for sand) - but this carries the risk of being underinflated on dry pavement, which may lead to a tire failure.

A further problem is that water freezes as high as 37°F and checking tire pressures below that temperature runs the risk of water freezing the valve open. To avoid this many people check their pressures when it is warmer and adjust the pressure in anticipation of what is to come by applying the 1 psi (2%) for every 10°F rule. That is if you are anticipating a 10°F temperature and you are setting your pressures in a 60°F garage, then you would overinflate them 5 psi (10%). Please note that overinflating a tire 5 psi doesn’t do as much harm as underinflating them 5 psi does. Wear and traction are largely unaffected by small overages.

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Had to go and complicate it didn’t ya.

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All weather, all purpose tire.

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Houston we have a problem!

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Normally you need more than 2 lb difference to set off a TPMS . 28-30 lbs maybe . 33 lbs , have no idea why that would cause it to go off unless one sensor is faulty .

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I completely disagree with that. You do NOT get better traction by floating on snow (which is what you’ll be doing when you lower pressure. I’ve seen people try this method in central NY (real snow country) and after 1-2 12"+ snow storms they realized it was extremely bad advice. Drive to places like Central NY or Upper Michigan where towns easily average 200" snow a year. Not one person who’s lived there for years or any tire dealer will tell you to lower tire pressure. Too much tire pressure isn’t good either. Keep tires properly inflated for optimum performance.

Winter Driving – Keep the Pressure On | S&S Tires (sstire.com)

Should you underinflate your tires in winter? | HowStuffWorks

As for the OP’s original question…That’s total nonsense. Winter tires MAY require a different pressure IF they are a different size then the summer tires (aka different footprint size). But no where near 20lbs difference.

Mmmmm … Tom and Ray seem to disagree with you:

https://www.denverpost.com/2006/04/22/deflating-tires-can-add-traction-but/

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The snow conditions they were talking about are very rare. Rarely do people drive on hard packed snow. We have these things called plows. So it’s either fresh snow or plowed snow/mush. I’ve driven half of my 1,000,000+ miles during winter months. I can count on 1 hand the number of times I drove on packed snow - and I live on a dirt road that isn’t plowed that well.

Oh contrair, not everyone lives in your neck of the woods. Many parts of the country do not get enough snow days to justify plows, so when it snows, we drive on packed snow. You can really divide the country into three parts, the northern band where they plenty of snow and are equipped for it, the middle band that gets only a little snow and are ill-equipped for it and the southern band that gets very little to no snow.

I’ve lived and travelled to many places, driving in snow can be different from one place to another.

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[quote="keith,
You can really divide the country into three parts, the northern band where they plenty of snow and are equipped for it, the middle band that gets only a little snow and are ill-equipped for it and the southern band that gets very little to no snow.

Agree I have seen it all in my working years.

Also agree I have driven in everything from a very light powder to whiteout condition’s

My worst experience was in El Paso, pulled in to the motel temperature in the high 60s, next morning six inches of snow. I10 had already been packed down to ice, no plows, no salt, no sand.

Mine too. Crossing New Mexico on I-10, bright shinny but cold morning. Saw the “Welcome to El Paso” sign, lit by the sun, but a fog bank literally feet behind it. Said to my wife, hope theres no ice in that fog. Glare ice all the way from there to Shreveport.

FWIW, if/when it does snow in Mississippi, you’ll either be driving on packed snow, or you’ll be the first person driving on it! We don’t get enough snow for it to make sense to purchase and maintain snow removal equipment. They do have enough equipment to remove snow from the interstate. But most of the side roads, they just let it melt. It’ll generally be gone within a few days anyway.

As far as tire pressure, I’m such a slacker that I usually don’t change mine for the week or two of snow that we get every 3 or 4 years!

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We have plows in Minnesota but after the plows clear the snow, the surface will be pretty slick until salt is applied. City streets are often snow packed until Spring. Just the way it is but we will all soon see for ourselves.

In Grand Forks ND, it was usually cold enough the snow did not turn to ice, a little sand on top and good to go on the packed snow.

In the city, as I remember, the plows spread sand&salt while they plowed. But that was many years ago. Biggest problem was digging out the driveway after the plows filled it.