airing down for snow

[Scooby]

I finally tried airing down in snow...However, I was in my Gl hatchback 4x4 but the theory applies just the same..

We were cruising in some soft snow on top some old tracks and I just went out of the track a few inches and promptly stuck myself...(dig or air down..?)
I wasn't hi centered just yet..so My partner and I aired down to 15psi(note we had our portable air compressors) . I did dig a small ramp to back out of the hole..
Then put it in gear a walked right out of what I just spinning tires in !!!

I had seen the jeepers do it with huge tires...but never thought the need would arise...

We aired back up and tried another route following a quad track which was abit narrower than mine and once again...stuck myself ...So again I aired down to 10 psi this time and walked right out of it...!!!

The biggest thing when airing down was the control we had and not so much bouncing around and we just floated over everything...Keep in mind ice and rocks, sticks make your tires targets for sidewall cuts! AT tires with more plies gives you abit of assurance...
Make sure to air down all the tires the same psi or your trans will hate you...Keep your speeds under 15mph...

[bjncj07]

I just recently was severely stuck in the snow/ sand and after some minimal digging and airing my highway terrain tires down to 10 psi. I to was able to drive right out of what appeared to be a rescue situation. Don't be afraid to air your tires down to assist in getting unstuck, just don't drive to far or fast before airing back up!

[amillion3]

What kind of air compressor do you two have? I'm looking for something that will play nice with the weak 12V outlet in my OBW.

[bjncj07]

The compressor I am currently using is a red Harbor Freight compressor with the exposed compressor, battery clips, and screw on tire valves, if I remember correctly it was about 50 dollars.( overall very happy ) My old compressor was a Campbell Hausfeld cheapie, which did do the job but just took 2-3 times longer than current compressor. Also on a different note: amillion3 I notice you installed some Fozzy struts, did that increase your height by more than an inch?

[John E Davies]

Originally Posted by bjncj07

The compressor I am currently using is a red Harbor Freight compressor with the exposed compressor, battery clips, and screw on tire valves, if I remember correctly it was about 50 dollars.( overall very happy ) My old compressor was a Campbell Hausfeld cheapie, which did do the job but just took 2-3 times longer than current compressor.

Is it this one? 1.35 cfm at 40 psi gets a normal sized tire filled very nicely without having to wait 15 minutes.

12 Volt, 150 PSI High Volume Air Compressor

I have a clone that I bought at a local auto parts store. It works fine for emergency use, but if I were _regularly_ going off pavement I would either carry an additional large volume hand pump (like a Blackburn mountain bike pump) as a backup in case the cheap electric pump quits, or invest the $$$ in a high quality 4wd pump (Ready-Air) or a small CO2 system (Powertank).

John Davies
Spokane WA

[reddoak]

A bit of an old thread bump here, but... I carry an 11 gallon air tank with me to air tires back up when I'm done. If it's full at 100 PSI, I can air all four tires (225/70/16) from around 15 PSI back up to 35 PSI without having to fire up a pump. I can strap it in the roof basket when I have that on, and a 25' coily air hose reaches all four tires, no problem.

I also have a high volume pump from Pep Boys that I carry in the back. LINK It would get the job done pretty quickly on it own, but it's far easier and quicker to just use the air tank on the side of the road or trail. Then I set up the compressor later to re-fill the tank when I have more time and space to work with. However, if the tank is screwed up for some reason, I have the air compressor. If the air compressor is screwed up, I have the tank.

If they are both screwed up.... I have a $10 "Harbor freight special" air inflator that would probably take 45 minutes to eventually get the job done. It's crap, but it's back up.


I use pre-set tire deflators to bring them down to around 20 PSI. Screw all four on the tire valves, by the time #4 is on #1 is usually done. Then I air them down to 15 with a pressure gauge. I could set them down to 15, but... they're not exactly precise. It goes pretty quick to let the last 3-5 PSI out manually and be sure of what they're at.

My arch-nemesis is sand, not snow. Airing down help a lot, I've found. And when you can air down in under 3 minutes, and air the tires back up in the same, you're far more likely to take the time before getting stuck. I found out the hard way how much getting stuck in sand sucks. I'd rather much around with tire pressure than shovels!

[Scooby]

Originally Posted by reddoak

A bit of an old thread bump here, but... I carry an 11 gallon air tank.

My arch-nemesis is sand, not snow. Airing down help a lot, I've found. And when you can air down in under 3 minutes, and air the tires back up in the same, you're far more likely to take the time before getting stuck. I found out the hard way how much getting stuck in sand sucks. I'd rather much around with tire pressure than shovels!

Given your 2011 outback is a heavy rig...reducing unneccessary weight would be in your favor.

I can air down with my dial guage in almost the same time without a special bleeder ..plus its more accurite. I am running a 215/75R15

Carrying that 11gal tank is not light....and two air compressors plus a blackburn pump . Unless your doing the Dakar rally(those rigs are nothing more than a shell/cage anyway..)

I have been wheelin for many years ..weight is the biggest issue with subarus . Given a small tire for flotation on sand and snow..it's a disadvantage.

I disagree with snow and sand being a different problem...they are almost identical . Firm and soft and everchanging...

Always travel in groups, as soon as you spin a tire.. stop and back out of it.
Speed and momentum are you friends on loose unstable surfaces.
Too slow and you dig in and are stuck quickly.
Finding that balance can be tricky at times.

I have been stuck in both so many times...I can't count ....
However, I get out quickly
Given I push the limits of my subie more than most sube enthusiasts...

[reddoak]

Originally Posted by Scooby

Given your 2011 outback is a heavy rig...reducing unneccessary weight would be in your favor.

I can air down with my dial guage in almost the same time without a special bleeder ..plus its more accurite. I am running a 215/75R15

Carrying that 11gal tank is not light....and two air compressors plus a blackburn pump . Unless your doing the Dakar rally(those rigs are nothing more than a shell/cage anyway..)

I have been wheelin for many years ..weight is the biggest issue with subarus . Given a small tire for flotation on sand and snow..it's a disadvantage.

I disagree with snow and sand being a different problem...they are almost identical . Firm and soft and everchanging...

Always travel in groups, as soon as you spin a tire.. stop and back out of it.
Speed and momentum are you friends on loose unstable surfaces.
Too slow and you dig in and are stuck quickly.
Finding that balance can be tricky at times.

I have been stuck in both so many times...I can't count ....
However, I get out quickly
Given I push the limits of my subie more than most sube enthusiasts...

I'll address the issues you mention and clarify:

Weight:
Lighter is better. No argument. That said, the 11 gallon tank is about 30 pounds, tops. The high volume pump is about 10. The little pump (think cigarette lighter powered bike tire pump, not a real compressor) is about 1 pound. I'm not carrying all that much, really. I can toss the worthless donut spare and darn near break even!

Deflating:
Sure, a dial gauge works fine. I don't particularly trust the calibration on the automatic deflators, either. So I set them around 20. All four work at once, I finish airing down with a pencil gauge to 15 psi. I just don't spend the whole time crouching next to my tires, is all. They aren't a necessity, just a convenience. Typically my 11 y.o. is with me, he puts them on, I finish the tire off, and he puts the caps back on. Keeps us both busy!

Everything else, yup. I'm certainly no expert, I don't claim to be. I'll defer to your experience. But I'm careful, and I believe in redundancy. So, that's why the tiny pump rides along. That's also why I carry two shovels if I'm headed off road. The weight penalty seems worth it to ensure I have what I need. I know it's overkill. But until I have more experience, I'm reluctant to pare down the off-road kit.

Most of the time this stuff lives in the garage. Weight kills fuel mileage on the road, too!

We took a "short-cut" to my parents house yesterday. All sand, not too loose, it's been driven on before. I've taken this path on 35 psi and 15psi, and it's night and day. The 35 psi is much more exciting, the tires dig in, the car wanders around on its own, and the engine strains noticeably more. At 15 psi, it's just a nice ride, gliding right through it... There are sections that are loose enough that I would not dream of stopping in them at 35 psi, they are much easier to navigate at 15.

I still wouldn't stop in these sections, though... Digging sand sucks.

Happy wheelin!