Maintaining proper pressure in the fifth tire

jamarimutt · 08-07-2004, 06:40 AM

Has someone tried to inflate and maintain proper presure in the skinny emergency-use tire? You have to take apart half the car to reach the tire, and when you do, the valve is facing down, meaning that the tire must be removed in order to check the tire pressure and/or inflate it!

My solution was to buy a small $10 battery compressor and store it with the tire. Now I can inflate the tire if and when I need to use it.

john1701a · 08-07-2004, 10:00 AM

Since you should routinely (twice a year) check the status of vehicle hidden areas anyway, which means taking out the spare tire, this is really a non-issue.

Inspecting seals is a good habit to get into. Discovering a tiny water leak a year or two after it began is not, but a lot of people do... usually when something starts to smell.

Be very thankful the spare-tire is stored inside the car. Thanksgiving 2 years ago was horrible. My uncle discovered had a flat early in the evening. The dark and cold set in before he finally gave up trying to get the spare free from its cradle hanging on the underside of the minivan. It has rusted in place, stuck so bad it later has to be broken off. How much PSI do you think was still in that tire?

jamarimutt · 08-07-2004, 01:59 PM

John: Like your uncle, I have never checked spare tire pressure. I considered starting with the Prius, but gave up because it's just too cumbersome. I belive that it's essential to carry a battery air compressor in this car, and probably all other cars.

I have owned many cars and have never checked the status of hidden areas.

ops:

DaveinOlyWA · 08-07-2004, 02:08 PM

doesnt the spare already have air in it??

i know that the door on my car says it should have 60 PSI in it...

Wolfman · 08-07-2004, 02:13 PM

Quote:

Originally posted by DaveinOlyWA
doesnt the spare already have air in it??

i know that the door on my car says it should have 60 PSI in it...

Yes, it will have air in it from the factory. However, it's normal for a tire to gradually lose pressure over time, even just sitting there unused. For that reason, you want to check it periodically to insure that it's still at the recommended pressure, especially after it's been sitting in that well, aging for a few years.

jamarimutt · 08-08-2004, 09:04 AM

I just went out and removed the spare tire. It wasn't as big a hassle as I thought it would be. Yo do have to remove (not just lift) the lockable cover, the plastic tray, and the jack. To check tire pressure you have to take the wheel out because the valve is facing down; if you put it back with the valve facing you won't be able to screw the jack tray to the tire.

Pressure was 43.5 pounds; the car was made in September 2003. I brought the pressure back to 60 and stored the compressor with the tire. One last thing... the spare tire's rim is painted the ugliest yellow you can imagine; you won't be leaving it on very long. :mrgreen:

I agree with John that it's much better to have the tire where it is than under the car.

LeVautRien · 08-08-2004, 02:45 PM

Why is it that the pressure on a spare has to be so much higher than that on a regular? Just curious.

john1701a · 08-08-2004, 04:00 PM

The extra PSI is to compensate for the design shortcomings of the tire (too thin, not reinforced). As a result, it is clearly not intended for anything but temporary use.

I personally don't think it is that much trouble to reach, since I am one of the few 2004 owners that has actually used the spare for real. I even jacked up the car to remove the damaged regular tire using the silly little scissor-jack. It worked surprisingly well.

DaveinOlyWA · 08-08-2004, 07:00 PM

previously in another car i had, i had a mini spare that was at some high PSI and the instructions said to deflate the tire to like 45 PSI from some higher figure. i always thought that this was done to take into account any pressure loss from extended storage.

of course it also said not to exceed 45 mph or drive more than 50 miles on the thing.

jamarimutt · 08-08-2004, 07:36 PM

Forgot to mention that the spare tire is a Bridgestone.

08-07-2004, 06:40 AM	#1
jamarimutt Senior Member Join Date: May 2004 Posts: 986 My Car: Model: Package: Thanks: 0 Thanked 3 Times in 3 Posts Friends: 0	Maintaining proper pressure in the fifth tire Has someone tried to inflate and maintain proper presure in the skinny emergency-use tire? You have to take apart half the car to reach the tire, and when you do, the valve is facing down, meaning that the tire must be removed in order to check the tire pressure and/or inflate it! My solution was to buy a small $10 battery compressor and store it with the tire. Now I can inflate the tire if and when I need to use it.

08-07-2004, 10:00 AM	#2
john1701a Senior Member Join Date: Jan 2004 Location: Minnesota Posts: 5,482 My Car: 2012 Prius Plug-in Model: Plug-in Advanced Package: No Package Thanks: 137 Thanked 956 Times in 498 Posts Friends: 22	Since you should routinely (twice a year) check the status of vehicle hidden areas anyway, which means taking out the spare tire, this is really a non-issue. Inspecting seals is a good habit to get into. Discovering a tiny water leak a year or two after it began is not, but a lot of people do... usually when something starts to smell. Be very thankful the spare-tire is stored inside the car. Thanksgiving 2 years ago was horrible. My uncle discovered had a flat early in the evening. The dark and cold set in before he finally gave up trying to get the spare free from its cradle hanging on the underside of the minivan. It has rusted in place, stuck so bad it later has to be broken off. How much PSI do you think was still in that tire? __________________ JOHN http://john1701a.com 3,140 miles 44.836 gallons 254.5 kWh 70.0 MPG (includes a 636 mile road trip)

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08-07-2004, 01:59 PM	#3
jamarimutt Senior Member Join Date: May 2004 Posts: 986 My Car: Model: Package: Thanks: 0 Thanked 3 Times in 3 Posts Friends: 0	John: Like your uncle, I have never checked spare tire pressure. I considered starting with the Prius, but gave up because it's just too cumbersome. I belive that it's essential to carry a battery air compressor in this car, and probably all other cars. I have owned many cars and have never checked the status of hidden areas. ops:

08-07-2004, 02:08 PM	#4
DaveinOlyWA 3rd Time was Solariffic!! Join Date: Apr 2004 Location: South Puget Sound, WA Posts: 14,711 My Car: 2010 Prius Model: IV Package: Solar Roof Thanks: 203 Thanked 519 Times in 375 Posts Friends: 14	doesnt the spare already have air in it?? i know that the door on my car says it should have 60 PSI in it...

08-08-2004, 09:04 AM	#6
jamarimutt Senior Member Join Date: May 2004 Posts: 986 My Car: Model: Package: Thanks: 0 Thanked 3 Times in 3 Posts Friends: 0	I just went out and removed the spare tire. It wasn't as big a hassle as I thought it would be. Yo do have to remove (not just lift) the lockable cover, the plastic tray, and the jack. To check tire pressure you have to take the wheel out because the valve is facing down; if you put it back with the valve facing you won't be able to screw the jack tray to the tire. Pressure was 43.5 pounds; the car was made in September 2003. I brought the pressure back to 60 and stored the compressor with the tire. One last thing... the spare tire's rim is painted the ugliest yellow you can imagine; you won't be leaving it on very long. :mrgreen: I agree with John that it's much better to have the tire where it is than under the car.

08-08-2004, 02:45 PM	#7
LeVautRien Senior Member Join Date: Jul 2004 Location: Claremont, California Posts: 367 My Car: Model: Package: Thanks: 0 Thanked 0 Times in 0 Posts Friends: 0	Why is it that the pressure on a spare has to be so much higher than that on a regular? Just curious.

08-08-2004, 04:00 PM	#8
john1701a Senior Member Join Date: Jan 2004 Location: Minnesota Posts: 5,482 My Car: 2012 Prius Plug-in Model: Plug-in Advanced Package: No Package Thanks: 137 Thanked 956 Times in 498 Posts Friends: 22	The extra PSI is to compensate for the design shortcomings of the tire (too thin, not reinforced). As a result, it is clearly not intended for anything but temporary use. I personally don't think it is that much trouble to reach, since I am one of the few 2004 owners that has actually used the spare for real. I even jacked up the car to remove the damaged regular tire using the silly little scissor-jack. It worked surprisingly well.

08-08-2004, 07:00 PM	#9
DaveinOlyWA 3rd Time was Solariffic!! Join Date: Apr 2004 Location: South Puget Sound, WA Posts: 14,711 My Car: 2010 Prius Model: IV Package: Solar Roof Thanks: 203 Thanked 519 Times in 375 Posts Friends: 14	previously in another car i had, i had a mini spare that was at some high PSI and the instructions said to deflate the tire to like 45 PSI from some higher figure. i always thought that this was done to take into account any pressure loss from extended storage. of course it also said not to exceed 45 mph or drive more than 50 miles on the thing.

08-08-2004, 07:36 PM	#10
jamarimutt Senior Member Join Date: May 2004 Posts: 986 My Car: Model: Package: Thanks: 0 Thanked 3 Times in 3 Posts Friends: 0	Forgot to mention that the spare tire is a Bridgestone.