Spare tire upside down

Does anyone know why the spare tire is mounted with the valve stem up? Is that to protect it from rocks breaking it off? They seem to gather more dirt and rust easier with valve stem side up. Has anyone tried to mount with valve stem down? Any issues? Thanks.

 

I used this to extend it to bottom so I can check and fill as necessary.

Slime 20140 Dually Tire Valve Extenders with Mounting Brackets

Slime 20140 Dually Tire Valve Extenders with Mounting Brackets

https://www.amazon.com/dp/B008FHWZIA?_encoding=UTF8

 

I assume it's so that the chain doesn't have to be extended so far. I put mine back on with the stem facing down just because I've had to change two flats and my spare wasn't as aired up as I like, so I make sure to fill it too.

 

Thanks. That's a good idea.

 

I keep mine valve stem up. Protects the face of my spare from getting beat up. Granted I have a full size spare with matching wheel so I don't want it dinged up and IF I had a steel rim spare I wouldn't care. I also have onboard air so if my spare is underinflated it's not a problem to air it up.

 

I put mine on face down, so I can check that it is full of air before trips etc. I have done this since at least 1977 and never had damage to the spare. YMMV

 

My $0.02. With the valve stem up, it’s easier to winch it up because all the mass is all on top. With the valve stem down, the tire keeps wobbling and doesn’t self center when you winch it up, you have to hold it still with your hand.

 

Like others have said, flipping it over allows you to check the pressure easily. I turned mine over and have had it up and down a few times and haven’t had and trouble with it coming loose, centering or wobbling.
I’d recommend soaking down the entire mechanism with Fluid Film (or whatever rust proofing you prefer) while it’s down. Also, try to put the valve at the very back so you can get to it without having to crawl under the truck to reach it....

 

Oh, so we are bringing common sense physics into this?

That might explain why my spare groaned when I cranked it back into place.

Time to flip it. Again.

 

It’s the nod to the Australian Hilux.

 

I thought it was mounted face up because of the mount used to secure it has a flat surface that butts up nicely against the flat surface on the back of the wheel without damaging it.

Might not be an issue for most, but I prefer to not gouge the finish on my aftermarket spare wheel (even if it is cheap). Can get a valve stem extension if needed to make this easier.

 

A better solution is to move the spare tire to the bed (if you don't need the space to carry cargo). Under the truck is a pretty bad place, for several reasons.

 

I always flip it upside down so I don’t have to pull the tire down to inflate it.

 

If the stem is up, then you have to exercise the lift mechanism in order to check it. Then there is less of a chance of it being seized when you really need your spare. Just my thoughts.

 

On my OR 2021 steel spare rim the hole next to the air valve is an oval which I believe allows something like this to access the valve when mounted in the up and less than accessible position.

$9 Milton Dual-Head Air Chuck, 1/4" FNPT, Tire Air Chuck for Tire Inflator Gauge and Air Compressor, S-690

Amazon.com: Milton (S-690 1/4" FNPT Dual Head Air Chuck : Tools & Home Improvement

 

I tried doing that, but my spares always went missing. Tacomas near me must get a lot of flat tires because people kept taking mine out of my bed… Now its back under the bed . Safe and sound..

 

doesn't everyone have an inflator they carry all the time?

 

I have started to fluid film every fall. So I take the spare out to do that then I coat to mechanism with some ff, check the tire and give the spare steel wheel a light spray too before putting it back in place.

may not be great only checking the tire once a year but better than people that never do an find it flat when they need it most.

I carry one often when I go out to the bike trails and camping. It’s only a 12v one. It’s come in handy though and you make new friends with others at the trail heads when you got air

 

The assumption for carrying the spare in the bed is having a camper shell or some other means of securing the tire. I wouldn't carry it exposed in an open bed.

 

Also needs to be secured too. Not wise to always carry it loose in the bed. It becomes a projectile in an accident.