How much air to put in temp spare

I would trust the manual.

There are a number of reasons not to run at max: Braking distance, handling, and ride comfort to name some, but the temp spare is not supposed to offer handling or comfort, it is to get you to a real tire.

 

I have never had a manual tell me not to run the temp spare at max pressure, can you give an example where one does?

 

These temp spares tend to lose PSI over time so set it at the recommended 60 PSI and check it every couple of months. The one in my 2016 Prii and my spouse's 2016 Subaru were both below 20 PSI as I had not checked either of them for a couple of years.

JeffD

 

I think we're trying to over-think this a little.

This isn't a passenger radial tire, it's a piece of damage-control equipment....just like a fire extinguisher.
If you use it...you're already not having a good day - and the idea is to use the spare to get you to a place where you can immediately get a replacement passenger radial tire, and maybe re-stow the spare for the next emergency.

I'd set it to 60, and check it in a few weeks.
If the pressure drops significantly....say much more than a couple of PSI, then setting it to 60psi didn't cause the problem, but rather you detected a pre-existing problem and you need to get another spare, and make sure that IT is inflated to the manufacturer's recommend pressure and it is able to maintain that pressure more or less.

I don't drive through very many sketch neighborhoods.....but I HAVE driven through some.
I do not often drive during extremely bad weather.....but it DOES happen on rare occasions, with me being a utility worker.
I don't really remember the last time I had to yank out a spare tire and mount it to get me back to the barn......but it HAS happened.

Murphy and Darwin are NOT limited to one unfortunate circumstance at a time.....so I don't limit MY options.
Spare tire....
Extinguisher....
First aid kit.....
Jumper cables.....
Charger pack....
EDC piece...WITH....a "spare" mag.


AS always.....
ACTUAL mileage WILL vary.

 

Manual says 60 psi, and that’s what I’d set it too. It’s sieve-logic to rely on the arrived pressure of an eBay purchase.

regarding:

there IS an age code on the sidewall. If it’s over 10 years I’d be thinking about replacing.

come to think of it: our 2010’s spare...

 

Anybody had much luck finding replacement tires of that size just as tires, as opposed to premounted on the matching rim?

I'm pretty sure the pressure requirement in the manual follows the fact that the tire is physically smaller, and needs the higher pressure to carry the designed load.

 

Tire rack had several candidates, last time I checked, and at least one looked a dead-ringer for the OEM tire. Can’t recall if it was same brand; that involves dragging it out to check.

come to think of it I should do that, check pressure and so on. I’ll take a pic of the make and model too.

AFAIK: the 3rd gen (16”) spare should also be compatible. 4th gen went to a 17” spare. The 16” size is very close to stock (195/65R15), while the 17’s undersized some.

 

15 inch spare in the uk

 

I fill mine to 80psi then in 3-6 months fill it up from 30-40psi back to 80psi

 

In 195/65R15? (aka full size)

 

Ok please ignore my last post.
Just checked and it’s a Falken T125/70D17. “Inflate to 60psi”

 

Some 3rd gen pics (as threatened); I think cross-compatible. Brace yourself, tractor-yellow rim:


(In above, is manufacture date the 29th week of 2009?)

For 3rd gen at least, stock size is 135/80D16 101M; here’s a tire rack prospect:
https://m.tirerack.com/tires/tires.jsp?tireMake=Yokohama&tireModel=Y870B&partnum=38MD6YOTEMP

 

As folks post temp spare pics, notice they do not say max pressure 60 psi, they say inflate to 60 psi. It does not sound optional. Just do it.

 

Agreed

 

1.) max load - it's a small tire, and if asked to be on the front for both braking and for cornering, the forces on the tire very well may approach max load - unless you have dead-straight roads. I'd have the pressure at 60 in case it does end up on the steer tires under unplanned hard cornering and braking conditions.

2.) Remember that tires leak air over time. Most of us find that checking a spare tire's pressure is a pain in the rear. Fill it to max, forget about it for a year, then check in a year - each year.