Air Down for What?!? Snow...

[MikeYQM]

I have a few questions for those in the snow belt regions, regarding airing down for various winter conditions.

I run a 2015 SR5 on KO2 275/70 17 E Rated at 40 PSI for on highway. I drive 50 km to work on primary and secondary highway and am “essential” so I gotta go, often before the plows get out. We often get snow/ice mix and slush but we do get dry powdery snow at times too.

My questions are:

1. Do you air down for different road conditions such as:
- dry snow
- wet snow
- ice
- slush

2. If so, how far down do you go?

I can see the benefit of airing down for deep snow but I see the potential of diminishing returns as the snow becomes slushy and hydroplaning becomes a factor.

Thanks


Sent from my iPhone using Tapatalk

 

[gm350reratliff]

I have a 28 mile one way drive to work near the continental divide and I'm usually on the road before the plows as well. That being said, I usually run about 32 psi in the rear and 35 in the fronts on most winter days. If I know it's going to be especially snowy, icy, slick, I may drop the pressures to 30 front/ 25 rear. This is on both 4runners, but I have an especially heavy front bumper on the front of the 4th gen. Also, I'm running ST Maxx on the 4th gen, Ridge Grapplers on the 5th gen. In my opinion, the RG's are better on the slick stuff.

 

[mrblah]

I have a few questions for those in the snow belt regions, regarding airing down for various winter conditions.

I run a 2015 SR5 on KO2 275/70 17 E Rated at 40 PSI for on highway. I drive 50 km to work on primary and secondary highway and am “essential” so I gotta go, often before the plows get out. We often get snow/ice mix and slush but we do get dry powdery snow at times too.

My questions are:

1. Do you air down for different road conditions such as:
- dry snow
- wet snow
- ice
- slush

2. If so, how far down do you go?

I can see the benefit of airing down for deep snow but I see the potential of diminishing returns as the snow becomes slushy and hydroplaning becomes a factor.

Thanks


Sent from my iPhone using Tapatalk

If you are going to do a lot of traveling before the snow plow comes out, you should get a set of snow tires, b/c driving on those roads is literally unpredictable as you don't know whats under the top layer of snow

 

[Jetboy]

It depends on how fast you are going. For highway speeds you need highway pressure. The lower the speed the lower you can go on pressure. I wouldn't go below 10 psi without bead locks.

Pressure and speed are primarily side wall heat concerns. There's no magic formula. For high speed desert running with 34" tires I would go as low as 20psi and as fast as 70mph. At 15 psi I'd stay under 30mph and mostly under 20. At 10 psi I'd keep it around 15mph max. That's in my 4runner. In my fj40 street pressure is about 20. Low snow pressure is more like 2-4psi. So it's not universal. Just my experience.

In my experience lower is always better for traction on everything from soft powder to ice.

Also remember that cold snow is much grippier than warm snow. Contrary to what you might think, icy snow packed roads in the north are generally not slippery. At 10 degrees packed snow covered roads have the same traction as a dry gravel road. The most slippery roads are when the temps are right near freezing. That's why you really don't need snow tires in northern climates as much as you might want them in somewhere like Colorado or utah where it's snowy but warm. As compared to somewhere like Montana or Minnesota where it's both snowy and cold.

 

[Guyerst]

Gotta admit that I'm surprised by the responses so far. There's times and places for airing down, but I've never even considered it in any type of snow.

Growing up in northern WI, I started racing in the ice races on frozen lakes at 10. In all conditions (hard cold ice, soft sun warmed ice, cold snow, slushy snow,...) we all would run skinny tires

40 years later, I don't believe you can beat a skinny set of heavily sipped snow/winter tires on the pavement in any condition below 40 degrees.

 

[nevada]

have you ran this set up in the snow yet?

as said about, there is no universal answer. every vehicle/tire/wheel combo will be different in regards to airing down for snow traction. but, universally you will have better traction with lower pressure, its just finding out what pressure works best for you specific scenario.

if 40 is the standard street pressure, I would recommend dropping down to 30 for snow/winter driving, and see how you like it. you can adjust from there based on your experience.

 

[Jetboy]

Gotta admit that I'm surprised by the responses so far. There's times and places for airing down, but I've never even considered it in any type of snow.

Growing up in northern WI, I started racing in the ice races on frozen lakes at 10. In all conditions (hard cold ice, soft sun warmed ice, cold snow, slushy snow,...) we all would run skinny tires

40 years later, I don't believe you can beat a skinny set of heavily sipped snow/winter tires on the pavement in any condition below 40 degrees.

You can test your theory. Air down one rear tire. Leave the other at full pressure. Turn off traction control and see which tire spins first. Do it a few times. Especially on something like a frozen lake. If higher pressure worked better, snowmobiles would look more like motorcycles.

 

[Chrisinvermont]

40 years later, I don't believe you can beat a skinny set of heavily sipped snow/winter tires on the pavement in any condition below 40 degrees.

:iagree:

Hakkapeliitta snow tires are what you need along with proper speed and snow driving technique. No need to be changing air pressures depending on if it's snowing or not. Much easier to do a tire swap in the fall instead of airing down and up depending on road conditions.

 

[loafer]

i have never aired down for winter driving. IF I start to slip then I adjust me speed. For the most part I would say that I have never experienced any problems. I just put smaller winter tires on the wife's runner, general grabbers and i am running the bf goodrich ta ko2. they both run pretty good in the winter.I do a lot of hunting so i put the miles on early before the plows and late in the day. Its a shame to see the idiots off on the side of the road in a ditch. every hunting season I see a few.besides if I air down the 2016 runner then I have to look at the low air pressure warning light. That would tweek my biscut.

 

[Jetboy]

Just to be clear - you should not be airing down for highway travel. Drive appropriately. Any all season tire will get you anywhere you need to go in the winter on normal highways with appropriate driving in a 4Runner. Airing down is for going off road. If you're sliding off the road - the problem is what's behind the wheel.

 

[MikeYQM]

Just to be clear, I wasn’t referring to a true “off road” air down, more so running slightly less pressure like in the 30 psi range.

I know speed is the biggest factor in winter driving safety. But if I can tune the truck to enhance traction given the reasonable speeds I’m already driving, I’m all for it.


Sent from my iPhone using Tapatalk

 

[graysquirrel]

The only time I have ever been told to air down my tires was driving on sand.

Never snow.

I live in Texas and drive up to Minnesota at Christmas time to visit family and I make sure that my tires have 35 to 36 psi in them when I leave Texas as with the change in the temp when I arrive in Minnesota they lose 4 to 5 psi.

Always drove with Michelin LTX or the new Michelin Defender and I have never had a problem driving in snow.

 

[Jetboy]

The only time I have ever been told to air down my tires was driving on sand.

Never snow.

I live in Texas and drive up to Minnesota at Christmas time to visit family and I make sure that my tires have 35 to 36 psi in them when I leave Texas as with the change in the temp when I arrive in Minnesota they lose 4 to 5 psi.

Always drove with Michelin LTX or the new Michelin Defender and I have never had a problem driving in snow.

Off road in deep snow airing down is the best traction and floatation option. It's night and day difference.

On the road, soft rubber and sipes are the formula for success. With high silicone content rubber and a good bit of siping a lot of all season tires are closing the gap on dedicated snow tires. The LTX is a great example.

A hard rubber mud tire with no sipes is probably about as bad as you could get. The old school MT tires were really terrible, which is why old farm trucks always relied on snow chains. Low pressure on modern tires will run circles around snow chains.

 

[4RN4FUN]

I was taught to drive in Minnesota, spent 9 years in Colorado and worked for Michelin and Bridgestone - my experience is: snow tires are the way to go if you want total confidence in knowing you have the best possible solution. Next, skinnier is better in snow. If you go with wider (lower pressure) to warm the snow, you better have a lot of sipes on your tires (which most AT tires don’t and no MT tire will).

Drive slow and drive smart when all else fails.



Sent from my iPad using Tapatalk

 

[charlatan]

:iagree:

Hakkapeliitta snow tires are what you need along with proper speed and snow driving technique. No need to be changing air pressures depending on if it's snowing or not. Much easier to do a tire swap in the fall instead of airing down and up depending on road conditions.

Hakka's are hands down the best winter tires on the planet. I don't own a 4R yet, but I've owned all sorts of sedans here in Colorado, and all my vehicles get Hakka's for winter.

And yes, the more narrow the tire, the better off you are on snow / ice. Weight distribution, or the lack of it on skinnys is the key.

Sent from my PH-1 using Tapatalk

 

[techno]

I'll echo what most replies say, tread pattern and tire type will have the biggest effect on your snow traction. But dropping psi down into the 30-35 range might help a little.

I think you'll have to experiment when the time comes. Your exact circumstances will ultimately have the final say.