It is a full size spare. The pressure is the same as all the other tires. I personally fill mine a bit higher than what I run on the other tires, because I don’t check the pressure on the spare often enough, so if and when I need it, I’d like it to have sufficient pressure.

FWIW, I think you should consider replacing the original tire, since it’s far past the age limit.

 

I agree with ajchien... if you still have the original full sized spare... you need to replace it... as it will probably go full "swiss cheese" on you if you ever have to actually use it due to age.

yeah it is stored and out of heat and sun.. but rubber simply does not age well even in mild ambient conditions. You would have to vacuum seal it in nitrogen (AND fill it with nitrogen) to stop it from simply degrading over time.

 

it will probably go full "swiss cheese" on you

My experience is that it will 'go out with a BANG'

If you have kept the tailgate-mounted spare 'naked' (no cover, that protects from UV rays) you are taking even more of a chance.

 

From all of your responses, I think I need to get a replacement. I haven't had it covered for several years. Is it important for me to get the same tire as the ones I have on the car already? Thanks!

 

whenever your tires wear out, some folks buy 4 new tires and ask the tire shop to use the “best old tire” as the spare. alternatively, some people like to do 5 tire rotations. I.e. they rotate the spare into the rotation.

 

Same size is VERY highly suggested if you have AWD.

 

Almost nobody ever checks their spare tire pressure. I'd keep a small 12v pump in the car if you traveled.

 

I do carry a Halo inflator/car jumper in my car at all times.