Author Topic: Why Air Down Your Tires Off Road  (Read 10558 times)

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Willard

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Re: Why Air Down Your Tires Off Road
« Reply #90 on: Oct 07, 2017, 03:45:32 PM »
I have been very lucky to not have any break downs in the past 6 years of hard wheeling. Not one single issue. It does happen to someone eventually and I'm always willing to lend a helping hand to anyone. I actually gave out 2 new u joints on the Rubicon and a spare stub for a 44. Never expected anything in return. Just good karma I guess. It's all part of the game of wheeling!


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blackdiamond [OP]

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Re: Why Air Down Your Tires Off Road
« Reply #91 on: Oct 09, 2017, 09:34:37 AM »
I picked up one of these over the weekend and will be headed out in a few to see how it handled the job.

https://www.4wheelparts.com/Air-Compressors-Air-Tanks-Air-Accessories/Smittybilt-2-54-CFM-Air-Compressor-2780.aspx?t_c=89&t_s=566&t_pt=100437&t_pn=S/B2780

Reading some of the links that Gnarly posted a wider tire doesn't have more traction, it simply give you a higher chance of achieving maximum traction.  This is because the friction force is independent of the surface area.

http://www.dummies.com/education/science/physics/how-surface-area-affects-the-force-of-friction/

What's interesting is that for sports cars going with wider tires give you a better opportunity to achieve maximum traction, but it allows a softer rubber compound to be used without wearing out any faster.

This, of course, is all things that could be shown in a lab environment.  The test I suggested earlier to measure how much pull a given rig could produce should, in ideal lab conditions, result in the same results at street pressure and aired down all other things being equal.

In the real world this is often not the case.  Another experience that my dad had was a nearly complete loss of traction from his BFG KMs on ice as they were nearly worn out.  The lugs lost their ability to flex and as a result couldn't not maintain traction on ice.  It was a drastic change from when they were new.  The rubber compound didn't really change, but the physical shape of the lugs had changed no longer allow them to have any flexibility.

When airing down off road you're increasing the surface area which increases the chances of achieving maximum traction while also making the treat more flexible which allows it to maintain contact longer which make it more likely that one lug won't lose traction before another engages.  Then you have the other benefits of airing down that include a softer ride, less impact load on your entire rig, better protection for the tire itself (in most cases).

If 300k is looking solely at the equations his argument is valid for a physics test, but because there are a lot more factors to be considered in the real world it doesn't translate to the point that the rubber meets the road.

 :driving:
1989 4Runner: Dual Ultimate (Inchworm front & Marlin 4.70 rear), Marlin Twin Stick, 1200-lb clutch, 4.88 R&P, Aussie Front, Detroit rear, 30-spline Longs, Long hub gears, ARP hub and knuckle studs & 35x12.50 Cooper STT PRO tires.  Marlin rear bumper & sliders.  FROR front bumper.  SAS with Alcan springs & Rancho 9000XL shocks.  Budbuilt Bolt-on traction bar.  Custom Interior Cage by Those Guys Rod and Customs.

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YooperYota

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Re: Why Air Down Your Tires Off Road
« Reply #92 on: Oct 09, 2017, 09:35:53 AM »
I definitely pointed out the surface area thing like 3 pages ago  :thumbs:

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blackdiamond [OP]

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Re: Why Air Down Your Tires Off Road
« Reply #93 on: Oct 09, 2017, 03:09:30 PM »
I picked up one of these over the weekend and will be headed out in a few to see how it handled the job.

https://www.4wheelparts.com/Air-Compressors-Air-Tanks-Air-Accessories/Smittybilt-2-54-CFM-Air-Compressor-2780.aspx?t_c=89&t_s=566&t_pt=100437&t_pn=S/B2780

Reading some of the links that Gnarly posted a wider tire doesn't have more traction, it simply give you a higher chance of achieving maximum traction.  This is because the friction force is independent of the surface area.

http://www.dummies.com/education/science/physics/how-surface-area-affects-the-force-of-friction/

What's interesting is that for sports cars going with wider tires give you a better opportunity to achieve maximum traction, but it allows a softer rubber compound to be used without wearing out any faster.

This, of course, is all things that could be shown in a lab environment.  The test I suggested earlier to measure how much pull a given rig could produce should, in ideal lab conditions, result in the same results at street pressure and aired down all other things being equal.

In the real world this is often not the case.  Another experience that my dad had was a nearly complete loss of traction from his BFG KMs on ice as they were nearly worn out.  The lugs lost their ability to flex and as a result couldn't not maintain traction on ice.  It was a drastic change from when they were new.  The rubber compound didn't really change, but the physical shape of the lugs had changed no longer allow them to have any flexibility.

When airing down off road you're increasing the surface area which increases the chances of achieving maximum traction while also making the treat more flexible which allows it to maintain contact longer which make it more likely that one lug won't lose traction before another engages.  Then you have the other benefits of airing down that include a softer ride, less impact load on your entire rig, better protection for the tire itself (in most cases).

If 300k is looking solely at the equations his argument is valid for a physics test, but because there are a lot more factors to be considered in the real world it doesn't translate to the point that the rubber meets the road.

 :driving:

For reference, the air down from 35 psi to 10 psi took under 2 minutes. The air up from 10 psi to 34 psi was right at 5 minutes. I think 3 minutes per tire will likely get really close to an acceptable all the time street pressure. The last few take a lot of time. The compressor gage is not accurate but seems consistent. 40 psi is about 35 psi.
1989 4Runner: Dual Ultimate (Inchworm front & Marlin 4.70 rear), Marlin Twin Stick, 1200-lb clutch, 4.88 R&P, Aussie Front, Detroit rear, 30-spline Longs, Long hub gears, ARP hub and knuckle studs & 35x12.50 Cooper STT PRO tires.  Marlin rear bumper & sliders.  FROR front bumper.  SAS with Alcan springs & Rancho 9000XL shocks.  Budbuilt Bolt-on traction bar.  Custom Interior Cage by Those Guys Rod and Customs.

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Slabzilla

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Re: Why Air Down Your Tires Off Road
« Reply #94 on: Oct 09, 2017, 07:14:23 PM »
I've been wheelin' more years than I care to admit and air down Every Trail. Anyone that doesn't is an idiot or a newbie or lacks the funds for some form of a device for adding air back after deflation, the ride is smoother the traction is better and the airing-up at the end of the trail is just part of the experience of the adventure.  If you have open diffs it's your best friend for getting further down that trail. In sand it keeps you on the top, in mud it's a great help too. Rocks are a requirement. Come to think of it I can't think of a good reason NOT to air down Off-Road, ever.  Get some real time out there and you'll find out yourself.   :twocents:  :twocents:   :twocents:
« Last Edit: Oct 09, 2017, 07:23:02 PM by Slabzilla »
'85 Xtra-cab, 4.5" Downey Off-Road lift, 12-15 KM2's on American Racing Baja's, 4.10's, 4.7's, Downey Off-Road CAI, Marlin rear bumper & sliders

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Re: Why Air Down Your Tires Off Road
« Reply #95 on: Oct 10, 2017, 04:03:21 AM »
I picked up one of these over the weekend and will be headed out in a few to see how it handled the job.

https://www.4wheelparts.com/Air-Compressors-Air-Tanks-Air-Accessories/Smittybilt-2-54-CFM-Air-Compressor-2780.aspx?t_c=89&t_s=566&t_pt=100437&t_pn=S/B2780


I haven't looked at ALL the 12V compressor options out there, but you know, for $100, that looks like a nice air-up option for any wheeler.  I'll be really curious how if works for you, reliability, and if you think it is worth the $100.  I'll buy one just to have in my truck as part of my off-road tool-kit.

Gnarls. :spin:

1986 XtraCab SR5 22RE 5speed W56B, ~10,000 MI after break-in, DIM (Did It Myself) rebuilt engine - .020" over, engnbldr RV head, OS valves, 261C cam, DT Header. https://imgur.com/oACTHTR

Slabzilla

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Re: Why Air Down Your Tires Off Road
« Reply #96 on: Oct 10, 2017, 11:53:41 AM »
I use the Smittybilts 5.4 cfm 12v pump, it airs up my 33's from 8 psi to my 25 psi street pressure, all four, in about 15 minutes including set-up.  I was going to set up an onboard air before I won this in a raffle. Now that I've used this I'd buy one of these in a heartbeat.  Some of the guys in my club have used it on their 35's and were amazed at the fill rate.  I'm happy.   :twocents:
'85 Xtra-cab, 4.5" Downey Off-Road lift, 12-15 KM2's on American Racing Baja's, 4.10's, 4.7's, Downey Off-Road CAI, Marlin rear bumper & sliders

blackdiamond [OP]

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Re: Why Air Down Your Tires Off Road
« Reply #97 on: Oct 10, 2017, 12:15:40 PM »
I use the Smittybilts 5.4 cfm 12v pump, it airs up my 33's from 8 psi to my 25 psi street pressure, all four, in about 15 minutes including set-up.  I was going to set up an onboard air before I won this in a raffle. Now that I've used this I'd buy one of these in a heartbeat.  Some of the guys in my club have used it on their 35's and were amazed at the fill rate.  I'm happy.   :twocents:

Mine is the model below it with a 2.54 CFM, I think.  I think I could get my 35s close to 25 psi in about 20 minutes.  I have not been motivated to do more than the single time trial of 10 psi to 40 psi on the gage (seems to be 34-35 psi on my accurate gage).  I might get bored at some point and try a fill based on time rather than gage pressure.  See what 3 minutes can get me.
1989 4Runner: Dual Ultimate (Inchworm front & Marlin 4.70 rear), Marlin Twin Stick, 1200-lb clutch, 4.88 R&P, Aussie Front, Detroit rear, 30-spline Longs, Long hub gears, ARP hub and knuckle studs & 35x12.50 Cooper STT PRO tires.  Marlin rear bumper & sliders.  FROR front bumper.  SAS with Alcan springs & Rancho 9000XL shocks.  Budbuilt Bolt-on traction bar.  Custom Interior Cage by Those Guys Rod and Customs.

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Slabzilla

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Re: Why Air Down Your Tires Off Road
« Reply #98 on: Oct 10, 2017, 12:39:24 PM »
I'm usually in no big hurry when airing-up, but if i'm B.S.ing and not paying attention this thing will overfill rather quickly.  I had a smaller one similar to yours and it gave me a lot more time to B.S. a bit before we got back on the road.  I always use my Accurate Bourdon Tube type gauge to check the final pressure, never rely on the pumps gauge.   :thumbs:  How do you like your Budbilt traction bar?
'85 Xtra-cab, 4.5" Downey Off-Road lift, 12-15 KM2's on American Racing Baja's, 4.10's, 4.7's, Downey Off-Road CAI, Marlin rear bumper & sliders

blackdiamond [OP]

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Re: Why Air Down Your Tires Off Road
« Reply #99 on: Oct 10, 2017, 06:08:53 PM »
I'm usually in no big hurry when airing-up, but if i'm B.S.ing and not paying attention this thing will overfill rather quickly.  I had a smaller one similar to yours and it gave me a lot more time to B.S. a bit before we got back on the road.  I always use my Accurate Bourdon Tube type gauge to check the final pressure, never rely on the pumps gauge.   :thumbs:  How do you like your Budbilt traction bar?

I am sold on the concept of the Budbuilt traction bar, but wouldn’t do it again. I was unable to really test it in Moab due to wet rocks that eliminated any chance of testing it on a couple of spots I had in mind. It ended up being a debacle to get installed for a non-fabricator (I do moonlight in the peanut gallery on occasion) like myself. Wouldn’t do it again but am happy to have it if that makes sense. Airing down is a bigger every time difference.
1989 4Runner: Dual Ultimate (Inchworm front & Marlin 4.70 rear), Marlin Twin Stick, 1200-lb clutch, 4.88 R&P, Aussie Front, Detroit rear, 30-spline Longs, Long hub gears, ARP hub and knuckle studs & 35x12.50 Cooper STT PRO tires.  Marlin rear bumper & sliders.  FROR front bumper.  SAS with Alcan springs & Rancho 9000XL shocks.  Budbuilt Bolt-on traction bar.  Custom Interior Cage by Those Guys Rod and Customs.

Moab Tested & Rubicon Approved

Gnarly4X

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Re: Why Air Down Your Tires Off Road
« Reply #100 on: Oct 10, 2017, 06:23:08 PM »
I use the Smittybilts 5.4 cfm 12v pump, it airs up my 33's from 8 psi to my 25 psi street pressure, all four, in about 15 minutes including set-up.  I was going to set up an onboard air before I won this in a raffle. Now that I've used this I'd buy one of these in a heartbeat.  Some of the guys in my club have used it on their 35's and were amazed at the fill rate.  I'm happy.   :twocents:

Good info!

I like the extra CFM... it's another $65, but when it comes to airing up, I'd pay the extra for almost twice the CFM... Probably last longer because it would not have to work as long on air-ups.

Gnarls.

1986 XtraCab SR5 22RE 5speed W56B, ~10,000 MI after break-in, DIM (Did It Myself) rebuilt engine - .020" over, engnbldr RV head, OS valves, 261C cam, DT Header. https://imgur.com/oACTHTR

emsvitil

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Re: Why Air Down Your Tires Off Road
« Reply #101 on: Oct 10, 2017, 06:50:45 PM »
Cheap air tank.........

The spare tire (if it's rated for 50psi, even better)

Just put 2 air valve quick disconnects on an air hose.     While you're pumping up first tire, you're using the spare to pump up the second.     You can even get some air out of the spare for the 4th tire while you're pumping up the third.
Ed
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Re: Why Air Down Your Tires Off Road
« Reply #102 on: Oct 11, 2017, 06:17:51 AM »
Cheap air tank.........

The spare tire (if it's rated for 50psi, even better)

Just put 2 air valve quick disconnects on an air hose.     While you're pumping up first tire, you're using the spare to pump up the second.     You can even get some air out of the spare for the 4th tire while you're pumping up the third.

emsvitil.... what were you smoking when you came up with this?   :screwy:

I know you were joking.  :thumbs:

I spent only about 10 seconds imagining how this would work and connect because I don't think there would be enough air pressure or pounds of air in my 33" spare tire at 50 PSI to only balance the air pressure between two tires.  If I connected, somehow, my spare tire with 50 psi to another tire that was at 10 psi, they theoretically may balance the air pressure between the two tires to 30/30.   :dunno:

But... I never underestimate the genius of the imagination. 

In the words of Albert Einstein... "The true sign of intelligence is not knowledge but imagination."

Gnarls.  :spin:




« Last Edit: Oct 11, 2017, 06:23:46 AM by Gnarly4X »
1986 XtraCab SR5 22RE 5speed W56B, ~10,000 MI after break-in, DIM (Did It Myself) rebuilt engine - .020" over, engnbldr RV head, OS valves, 261C cam, DT Header. https://imgur.com/oACTHTR

H8PVMNT

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Re: Why Air Down Your Tires Off Road
« Reply #103 on: Oct 11, 2017, 07:15:05 AM »
No the hose on the spare works great. When we used 33s we would use a 10 ply spare of similar diameter and put it to max psi.  Rigged up the locking chuck on one end of a coily hose and a regular chuck on the other.  120 psi in a spare was plenty enough to get 4 33x12.50s from 8 psi to mid to high 20s.

We finally quit when mu buddy's vintage spare exploded in his garage.  Still a good method if you ask me just use a fresh spare :).
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300k

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Re: Why Air Down Your Tires Off Road
« Reply #104 on: Oct 11, 2017, 10:37:50 AM »
No the hose on the spare works great. When we used 33s we would use a 10 ply spare of similar diameter and put it to max psi.  Rigged up the locking chuck on one end of a coily hose and a regular chuck on the other.  120 psi in a spare was plenty enough to get 4 33x12.50s from 8 psi to mid to high 20s.

We finally quit when mu buddy's vintage spare exploded in his garage.  Still a good method if you ask me just use a fresh spare :).

that seems so sketchy, i like it! lol
Keep it TOYOTA!

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blackdiamond [OP]

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Re: Why Air Down Your Tires Off Road
« Reply #105 on: Oct 11, 2017, 11:16:40 AM »
that seems so sketchy, i like it! lol

You could apply some physics and go  Baja style with two spare tires.  With some volume measurements and some calculations you could setup one spare tire to be connected to the other four and allow them all to equalize at your desired low air pressure (maybe 35 psi for you  :gap:).  The other would be the reverse that would allow all five tires to equalize at the desired street pressure.
1989 4Runner: Dual Ultimate (Inchworm front & Marlin 4.70 rear), Marlin Twin Stick, 1200-lb clutch, 4.88 R&P, Aussie Front, Detroit rear, 30-spline Longs, Long hub gears, ARP hub and knuckle studs & 35x12.50 Cooper STT PRO tires.  Marlin rear bumper & sliders.  FROR front bumper.  SAS with Alcan springs & Rancho 9000XL shocks.  Budbuilt Bolt-on traction bar.  Custom Interior Cage by Those Guys Rod and Customs.

Moab Tested & Rubicon Approved

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Re: Why Air Down Your Tires Off Road
« Reply #106 on: Oct 11, 2017, 11:50:50 AM »
"We finally quit when mu buddy's vintage spare exploded in his garage.  Still a good method if you ask me just use a fresh spare :)."


Well… I’ll tell you what I think about that.

First…. H8PVMNT… that post dropped your I.Q down about 20 points! LOL…..  Somewhere just above a retard.

You went from “Master Tweaker”, to “Master Twit”.. LOL.

Secondly, I would NOT want to pump up my spare 2.5 times above the maximum rated – not only because of the obvious danger of exploding and causing some serious injury or damage, but also because the stress may make the tire structure fail prone.

Thirdly, buying the necessary connectors and hoses would cost more than a 5 gallon compressed air tank.

And, lastly…. I would have to witness a 33x12.50 tire at 120 psi produce enough volume of air to air up 4 tires from 8 PSI to 25 PSI… I don’t think there is enough volume of air (cubic feet of air) in that tire.  You would need about 2 cubic feet of air, which is about 15 gallons, or 3 each 5 gallon air tanks, filled to about 150 PSI each.

Of course, anything is possible on 4-wheeling forums, and I could be sucking air somewhere.  :yikes:

Gnarls.  :gap:
1986 XtraCab SR5 22RE 5speed W56B, ~10,000 MI after break-in, DIM (Did It Myself) rebuilt engine - .020" over, engnbldr RV head, OS valves, 261C cam, DT Header. https://imgur.com/oACTHTR

blackdiamond [OP]

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Re: Why Air Down Your Tires Off Road
« Reply #107 on: Oct 11, 2017, 04:50:05 PM »
Maybe he’s a Patriot fan and will accept slightly deflated tires.
1989 4Runner: Dual Ultimate (Inchworm front & Marlin 4.70 rear), Marlin Twin Stick, 1200-lb clutch, 4.88 R&P, Aussie Front, Detroit rear, 30-spline Longs, Long hub gears, ARP hub and knuckle studs & 35x12.50 Cooper STT PRO tires.  Marlin rear bumper & sliders.  FROR front bumper.  SAS with Alcan springs & Rancho 9000XL shocks.  Budbuilt Bolt-on traction bar.  Custom Interior Cage by Those Guys Rod and Customs.

Moab Tested & Rubicon Approved

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Re: Why Air Down Your Tires Off Road
« Reply #108 on: Oct 11, 2017, 05:55:51 PM »
"We finally quit when mu buddy's vintage spare exploded in his garage.  Still a good method if you ask me just use a fresh spare :)."


Well… I’ll tell you what I think about that.

First…. H8PVMNT… that post dropped your I.Q down about 20 points! LOL…..  Somewhere just above a retard.

You went from “Master Tweaker”, to “Master Twit”.. LOL.

Secondly, I would NOT want to pump up my spare 2.5 times above the maximum rated – not only because of the obvious danger of exploding and causing some serious injury or damage, but also because the stress may make the tire structure fail prone.

Thirdly, buying the necessary connectors and hoses would cost more than a 5 gallon compressed air tank.

And, lastly…. I would have to witness a 33x12.50 tire at 120 psi produce enough volume of air to air up 4 tires from 8 PSI to 25 PSI… I don’t think there is enough volume of air (cubic feet of air) in that tire.  You would need about 2 cubic feet of air, which is about 15 gallons, or 3 each 5 gallon air tanks, filled to about 150 PSI each.

Of course, anything is possible on 4-wheeling forums, and I could be sucking air somewhere.  :yikes:

Gnarls.  :gap:


Gnarls you doad.  Read the post brainiac   :disturbed:! I used a 10 ply spare.

The 10 ply 235/85 r16 load range E spare had a max inflation of 120 psi. 

I would not do this with a 33x12.50 6 ply rated for 35 psi max that would be asking for it.  If that's what you got out of that you should think I was a reetaard! I don't even blame you, just put on your specticals.

And just for clarification for the calculator police, I don't think it will top off 4 tires from low pressure to low-mid 20s psi, it DID top off 4 tires from trail pressure to low-mid 20s psi.  I even reseated a bead with it a time or two with the help of a ratchet strap.  Compressed air is compressed, so if you use a load range E for a spare maxed out you get a lot of air out of it.  I don't make a habit of posting speculation.

Oh and 300K, don't be doing this with your 6 ply re-treads spare, you will blow your head off!  10 ply spare, 10 ply spare, 10 ply spare, load range E max psi 120...

Now you've gone and done it.  I have burned my Brussel sprouts because I had to reply.
« Last Edit: Oct 12, 2017, 03:42:25 AM by H8PVMNT »
“I would rather wake up in the middle of nowhere than in any city on earth.”
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"I plan to hit 300k in this truck"  :)bestgen4runner

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Re: Why Air Down Your Tires Off Road
« Reply #109 on: Oct 11, 2017, 06:12:17 PM »
Now you've gone and done it.  I have burned my Brussel sprouts because I had to reply.

ooh, i'd almost feel bad if it was something other than brussel sprouts...YUCK!
Keep it TOYOTA!

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Re: Why Air Down Your Tires Off Road
« Reply #110 on: Oct 11, 2017, 08:03:49 PM »
  If I connected, somehow, my spare tire with 50 psi to another tire that was at 10 psi, they theoretically may balance the air pressure between the two tires to 30/30.   :dunno:


Which is 20 psi you don't have to pump up with the air pump.


One of these (or whatever is currently cheapest)

https://www.harborfreight.com/38-in-x-8-ft-15-ft-rubber-air-hose-remnant-61942.html

Two of these:

https://www.harborfreight.com/tire-chuck-with-lock-on-lever-62626.html


And use your 20% coupon.




Ed
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31x10.50R15

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Re: Why Air Down Your Tires Off Road
« Reply #111 on: Oct 11, 2017, 11:31:44 PM »
Hi guys, I don’t post much around here.  If you don’t mind i’ll Chime in.

I’m military and have 14yrs offroading.  The nice thing about moving around and wheelin is seeing the difference flavors of off-roading.  I’m currently stationed in upstate NY, current deployed as rotational force (non-combat deployment) I head home next week!!!!!  So the local club in Watertown loves mudding; I mean big V8s, 40/44 tires, on open Dana 44 f/r, tall lifts mostly from lift blocks.  These guys laugh at me airing down.  But they are at polar opposite of my wheelin preference.  Well maybe not as polar opposite to me as mall crawlers but you get the picture.  For them they don’t want traction they want/need wheel spin.  Otherwise they break stuff.  Couple other groups around that wheel my flavor of trails and obstacles and each one of their rigs gets aired down.

Gnarly4X

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Re: Why Air Down Your Tires Off Road
« Reply #112 on: Oct 12, 2017, 03:36:33 AM »


Hey muddpigg,

First, I realize you may hear this often, but Thank YOU for your service to our Country.  :usa:

I have a military family and fortunately and by the Grace of God, so far, I've only had to sit
through one military funeral.  :usa:

14 years of wheeling gives you a pretty good perspective on the hobby/sport.  :beerchug:

The mud boggers know what they are doing.  So for 300k.... perhaps mud bog'n would be fun.  :gap:

Gnarls.  :smokin:
1986 XtraCab SR5 22RE 5speed W56B, ~10,000 MI after break-in, DIM (Did It Myself) rebuilt engine - .020" over, engnbldr RV head, OS valves, 261C cam, DT Header. https://imgur.com/oACTHTR

Gnarly4X

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Re: Why Air Down Your Tires Off Road
« Reply #113 on: Oct 12, 2017, 04:21:32 AM »
Gnarls you doad.


Hey H8PVMNT,

Geeezz… I’m learning Montana slang.. .I had to Google DOAD…. Yes… sometimes I feel like a giant 188 pound doad!  There are other, bigger, well-known doads here on the forum.  :moon:

I’m a communications analyst, all day long I read computer-generated text data, ASCII characters… so yeah, I caught your “6 ply”.  :gap:

I was good up to the end when you said your buddy blew up a 6 ply tire!  :willynilly:

And, no, you don’t post poop and stink…. Some pomp.  :beerchug:

And yes, I was sure you DID fill up some tires with that tire bomb… although I would still like to see it.  With that said, the things I’ve seen done and fixed on a trail would defy many 100-year old equations written by some old gray-haired geek scientist.  :inthedark:

You, being around a “buddy” that uses an exploding 300-year old 6-ply tire as compressed air tank, doesn’t sound like you.  So, could the filling to max repeatedly cause the tire to explode?  :dunno:

The reason I threw you a tease-bomb is to bring the idea to a level of “that’s-really-NOT-a-good-idea”.  Here in AZ that person would be considered by many to be a "reetard", and probably would not be allowed on a run. :thumbdown:

YOU know that a 6-ply tire can take 120 PSI, but you also know that someone else reading these posts could go out tomorrow and fill up their 33” BFG ATs to 120 lbs.!!!  :shake:

I think there are enough inherent potential dangers while wheeling that carrying a tire bomb is NOT a good idea… that’s just weird thinking for a DOAD.  :gap:

Regarding your I.Q. …. Even if it were to take a 20 point dip, you are still one of the sharpest knives in the draw.  And I believe I’ve said this before, my Toyota knowledge and experience would not make a pimple on your butt!  :bowdown:

Halloween is coming… I’m going to WalMart and look for a DOAD costume!!  :disturbed:

I feel very badly about you burning your brussel sprouts because you were communicating with a doad!  :rivers:

Gnarls….lots of pomp ‘n stink.  :wave:




« Last Edit: Oct 12, 2017, 06:50:46 AM by Gnarly4X »
1986 XtraCab SR5 22RE 5speed W56B, ~10,000 MI after break-in, DIM (Did It Myself) rebuilt engine - .020" over, engnbldr RV head, OS valves, 261C cam, DT Header. https://imgur.com/oACTHTR

blackdiamond [OP]

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Re: Why Air Down Your Tires Off Road
« Reply #114 on: Oct 12, 2017, 05:36:53 AM »
How is having a spare tire aired up to maximum rated pressure qualify as having a “bomb”?  I keep my spare close to the max 35 psi. If it’s an old worn out brittle tire then it should be replaced for multiple reasons.
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muddpigg

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Re: Why Air Down Your Tires Off Road
« Reply #115 on: Oct 12, 2017, 06:27:19 AM »
Hey muddpigg,

First, I realize you may hear this often, but Thank YOU for your service to our Country.  :usa:

I have a military family and fortunately and by the Grace of God, so far, I've only had to sit
through one military funeral.  :usa:

14 years of wheeling gives you a pretty good perspective on the hobby/sport.  :beerchug:

The mud boggers know what they are doing.  So for 300k.... perhaps mud bog'n would be fun.  :gap:

Gnarls.  :smokin:


Thanks for the appreciation and back at you.  14yrs of wheelin but started with a zero automotive education so been slow.  I like the tech over here and find myself lurking more and more.  Won't pull a newb move and post something non relevant here.

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Re: Why Air Down Your Tires Off Road
« Reply #116 on: Oct 12, 2017, 06:53:07 AM »
How is having a spare tire aired up to maximum rated pressure qualify as having a “bomb”?  I keep my spare close to the max 35 psi. If it’s an old worn out brittle tire then it should be replaced for multiple reasons.

According to H8PVMNT, his buddy he was unable to figure out WHEN his 6-ply tire would turn into a bomb?  :gap:

Gnarls.  :driving:
1986 XtraCab SR5 22RE 5speed W56B, ~10,000 MI after break-in, DIM (Did It Myself) rebuilt engine - .020" over, engnbldr RV head, OS valves, 261C cam, DT Header. https://imgur.com/oACTHTR

H8PVMNT

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Re: Why Air Down Your Tires Off Road
« Reply #117 on: Oct 12, 2017, 07:50:37 AM »
Yeah it was way old, like a cool late 60s mud terrain with some sweet weather checking.  A real museum piece for sure. To be fair he is a jeep guy.  He only did like 100 psi I think and the story was he heard a big bang in his garage, he went in to investigate and the tire had alligatored and peeled his rack and spare tire carrier right off the jeep.
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63W

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Re: Why Air Down Your Tires Off Road
« Reply #118 on: Oct 12, 2017, 07:55:04 AM »
Just look at semi trailers when they blow a tire. They will rip metal apart.


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Re: Why Air Down Your Tires Off Road
« Reply #119 on: Oct 12, 2017, 07:55:24 AM »
Man this thread has some traction, despite being aired up to street pressure and beyond...
“I would rather wake up in the middle of nowhere than in any city on earth.”
– Steve McQueen

"Except for maybe Seattle."  -H8PVMNT

"I plan to hit 300k in this truck"  :)bestgen4runner

 
 
 
 
 

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