Spare tire psi?

[Mall'er]

What pressure do you run on your spare?

I keep 8 psi in my spare, as I expect I will most likely need it on the trail, and don't want to muck with airing it down. I do have OBA, so airing up is not an issue.

What psi do you run, and why?

CO2 guys, do you run a full pressure tire for a spare?

 

[Rut Row]

I don't keep any spare PSI, I use it all

I tend to keep mine at 30#. It is easier to air down then air up.

 

[Apparition]

Do you drag it on rocks? If so I’d keep it low and air it up as needed.

If not then road pressure would make the most sense to me.

 

[MutantNinjaTJ]

I don't keep any spare PSI, I use it all

I tend to keep mine at 30#. It is easier to air down then air up.

What he said!

 

[Mr. Bills]

My spare is at street pressure.

Back in the day before everyone and their cousin carried an air compressor, it was often advocated by experienced desert rats to fill the spare to the maximum pressure listed on the sidewall or even higher in order to "rob" pressure from the spare for a tire on the ground. During the 1970's and early 1980's, Harry Lewellyn, who later developed Coyote Deflators, sold a length of air hose with screw on fittings on each end for that purpose. It had a catchy name which I have forgotten.

 

[Jerry Bransford]

If your TJ is a trailer queen you can keep the spare at your trail psi though I'd keep it a little higher just since tires tend to lose air pressure. But if you drive your TJ on the street too as I do I'd keep the spare just above the usual street pressure since, again, tires tend to lose pressure and most of us don't check the air pressure in the spare as much as we do the tires on the ground.

 

[freedom_in_4low]

On the Jeep, I keep it at street pressure.

My other vehicles, 0 psi apparently, based on them always being flat when I actually need them.

 

[Jerry Bransford]

On the Jeep, I keep it at street pressure.

My other vehicles, 0 psi apparently, based on them always being flat when I actually need them.

The last time I needed my spare, a couple years ago in Arizona after a rock tore a hole in its sidewall, naturally my spare tire had gone flat even after checking/adding air several weeks earlier. It was so old and stiff that it stopped being able to remain seated against the bead. Several offers of a spare tire loan didn't work because I have 5x5 bolt pattern wheels so it took probably 30-60 minutes to get the spare so it'd hold air again.

Then I was told that Goodyear had discontinued the 35x12.50R15 MT/R so it took me 3-4 months to find a replacement. My local Discount Tire store finally found one near the East coast and had it shipped out to me for free, I was THANKFUL. I think I got the last one in the US, they couldn't find one more for me.

 

[freedom_in_4low]

The last time I needed my spare, a couple years ago in Arizona after a rock tore a hole in its sidewall, naturally my spare tire had gone flat even after checking/adding air several weeks earlier. It was so old and stiff that it stopped being able to remain seated against the bead. Several offers of a spare tire loan didn't work because I have 5x5 bolt pattern wheels so it took probably 30-60 minutes to get the spare so it'd hold air again.

Then I was told that Goodyear had discontinued the 35x12.50R15 MT/R so it took me 3-4 months to find a replacement. My local Discount Tire store finally found one near the East coast and had it shipped out to me for free, I was THANKFUL. I think I got the last one in the US, they couldn't find one more for me.

View attachment 456237

I do a 5 tire rotation on the Jeep so the spare gets fairly regular attention, and I've had to use it, but mostly preemptively, like I spot a nail and swap on the spare to take it to the shop and get patched.

Last time I needed one in a daily driver I was hauling some friends and our dirt bikes back to eastern Oklahoma from SW Colorado in an F150 I had back then. We stopped in Clayton, NM for lunch and came outside to find one of my rear tires with sidewall blisters all the way around. Spare was probably original, flat, dry and severely cracked....and it was Labor Day.

Somehow the only tire shop in town was OPEN and had a selection of used tires including a pair in the right size so I paid something like $60 to get them mounted on the rear wheels of my truck to get me home where I promptly bought 5 new 33" BFG KOs. Sadly that tire shop closed down within a year or two and the tire shop/service station building has been vacant since.

I'm knocking on wood but that's a pretty good run, 12 years since I've had to change a tire on the road.

 

[KennethS]

My spare is the best of the previous 4 tires, and while it's the same size as the four on the ground, it's a different manufacturer and has a tire cover to protect it from the brutal Arizona sun. The pressure gets checked annually at oil change / tire rotation time, so I air it up to near 40 PSI as by the time I need it the pressure will likely have decreased to "nominal" street pressure of around 26 PSI.