How much air to release from tires when stuck in deep snow?

[nobb]

A few weeks ago when we had the big snow storm, I got my fwd car stuck in snow (it had blizzaks) trying to go through some of the un-plowed communities. Rubber mats underneath the front drive wheels and pushing didn't work, so I spent about 2 hrs digging it out.

I think potentially I could have gotten out much faster if I had just released some air from the tires. Or I wonder if digging would have even been necessary. I have a spare air pump in the back so I can just re-inflate the tires after.

So the question is, down to what psi should you release the air out from your tires down to for maximum traction to get out when stuck in snow? Or would it even work better, because in some situations (like mine), the snow props up your car from underneath and what you want is more ground clearance over traction.

[410440]

I doubt letting air out would have helped all that much anyway, the snow was so deep and slushy that anything with low ground clearance was already hooped.

[Zero102]

If you let air out of your tires they get shorter, not taller. This means that when you are high centered on snow your tires will have even less traction. I don't think that is what you want to do in this situation. Best bet is either a tow truck in a box or a shovel when you are high centered.

[89s1]

Agree with the posters above.

If your logic was based off the things you saw on the top gear polar special there was a reason it worked for them. The snow was hard and crusty, and their tires were quite large to begin with.

You'd be better off with a taller, narrower tire in typical snowfall, as has been stated above.

For instance, on a civic I run 185/65/15 in the winter, versus 205/50/15 in the summer.

[nobb]

^Haha yea, I just watched the top gear polar ice special, and that's why I was curious as to the effect releasing air on tires would have for a typical city driving situation. There were some situations where it seemed the Hilux was propped up on snow as well.

[ExtraSlow]

I agree with the posters above. "airing down" is used on off road vehicles to increase the surface area of the tires. Works fine on snow and sand, as long as the vehicle has sufficient ground clearance.
In a low car, on unplowed city streets, you are probably high-centered, so this technique wouldn't help at all.

[AE92_TreunoSC]

I've done it in desperation sometimes with positive effects, it depends on the scenario.

I stick my key in the valve stem and air the tyres out to 25psi, or about 10 seconds of air release.

It helped me after I foolishly set my tyres to 35psi (5 above my spec with all seasons and a torquey fwd car) and tried to get through an alley full of thick snow in my car. Visited a gas station later and set them to 30 even.

[Stealth13]

It would only work if the car was not high
centred

[revelations]

Ya I did it once with my truck when I had summer-only tires :eek:

Went from 30-20 psi and it made a noticeable difference in handling - and a noticeable drop in fuel economy!

[spikerS]

in winter time, this is about the dumbest thing you can do.

it is a misconception that in winter time with snowy/icy roads, that the more rubber you have making contact, the more traction you have. What people forget is, the more rubber you have making contact, the less downward force you have per square inch, thus less friction (traction). In winter you want narrow tires to "cut through" the ice and snow, and with the narrow tires, it allows for more downward force per square inch.

interesting fact.

A 100lb woman wearing shoes that have a 1/4"x1/4" footprint, will exert more downward force than an M1A2 Abrams tank.

[Rat Fink]

.

[nobb]

Hmm, good point about the narrow tires. But one thing to note about having a narrow tire for a low ground clearance car is that youll sink into the snow more, which could be a disadvantage when driving through deep packed snow since youll increase the chances that a big block of snow will wedge underneath your car and prop you up.

[canuckcarguy]

And are Blizzaks snow tires or ice tires? Ice tires are awesome on the ice, but don't always get you out of a snow drift. I think shoveling might have been your only option.

[bituerbo]

2 wooden snowbrushes ($1.97) > 1 magnesium alloy telescoping unit ($20).

Jam 1 under each drive wheel. I've aired down with success before, but I trying to get uphill on a very slick surface.

[adam c]

i saw these at canadian tire when i was xmas shopping, the video they were playing looked pretty good
http://www.canadiantire.ca/search/search_results.jsp?bmForm=form_endeca_search&bmFormID=1262189673847&bmUID=1262189673847&bmIsForm=true&bmPrevTemplate=/AST/ResearchCentre/winterdriving.jsp&bmHidden=OMNITURE_FROM&OMNITURE_FROM=Search&bmText=quick_search_term&quick_search_term=tow+truck+in+a+box&bmSubmit=quick_search&quick_search=Search&bmHidden=FOLDER%3C%3Efolder_id&FOLDER%3C%3Efolder_id=1408474396678203

[Zero102]

The only problem with a tow truck in a box, is if you wedge it in such that there is some space under it, when your wheel gets to that point the board will bend or crack and break. Also, if you dug a bit of a hole under your wheel sometimes you cannot fit them in because they will hit the underside of your car.

Basically, carry a shovel with them and re-arrange the snow as necessary to fit them properly, don't just jam them under the wheels and hope for the best. When used properly they are excellent and have been a huge help for myself and others in the past :thumbsup: