When we got the TPMS for the trailer, I got it with six sensors. Since the truck already had TPMS installed, I put four on the trailer, one on the trailer spare and one on the truck spare. Now I don’t have a need to crawl under just to check the pressure. Towing the trailer is just about all I use the truck for, so the TPMS solution works out great for me.

 

But if it's stored valve stem down doesn't the air fall out?

 

If you use teflon tape on the threads of the valve cap it holds it in.

 

I have my valve up, that way there it gives me an excuse to use the spare tire winch. I also smear grease on the rim to prevent it from rusting. On my last Super Duty I wanted to check the spare tire and the winch was froze, used a die grinder to cut' the cable. Fortunately I was home when I tried it and not on the side of the road. Now I check my winch at least once a year. Living in the rust belt has its drawbacks.

 

Aha!...noted.

 

And that is why I check my spare tire pressure every oil change, I consider that tire flat. I do not want to be in a situation where I have to put a 32 psig spare tire on a position that should be 65 psig or 80 psig, and I have to travel down the highway pulling a 12K# camper. Is it really that much trouble to check the spare tire pressure every oil change? Oh, and I put my spare tire valve stem in the down position. Philip.

 

With the valve stem down, Its easier to change from winter air to summer air......

 

Former AAA fleet driver... you would not believe the number of spare tires I pulled out of trunks and from under trucks and vans that were next to flat. Just check it time to time, make sure something is in it. Take it to max inflation on the tire, and then check it again a year later.

 

Leave the valve stem up so you can drop the cable once a year and check it. Wife was driving her expedition one day when she felt a bump. Looked in the rear view and saw her spare tire bouncing down the road. By the time she turned around and went back, someone already stopped and took it. The cable had rusted through and the spare fell off.

 

Until my current truck, I have never even dropped the spare tire on a vehicle. I have had 11 vehicles so far that would have had a full size spare on a winch cable. This truck is the exception, as I had a defective wheel from the factory and my passenger side inner dual would not hold air because the rim was dented at the lip of the bead. How this passed the dealership "prep", I have no idea. I found it when I brought it home and decided to check air pressures because something felt wrong out back.

Anyway, my point is, I have never needed the spare, but also never cared whether it was flat or not. I carry an air compressor in all of my vehicles, offroad ones too. If I need a spare, it's because I couldn't get a plug to hold air in it long enough to reach my destination. If that's the case, it is likely a sidewall tear, which isn't happening unless I am doing something I shouldn't be with that tire, or I ran it underinflated and it blew out. Neither of which I do, because I make sure to monitor my tire pressures often.

I guess what I am saying is this, I don't understand why nobody in this thread has mentioned that they carry a compressor instead of relying on a spare to hold air, and the winch not to rust in place, etc. I carry a good compressor and plug kit as cheap insurance, with the hope I will never have to use the spare. To each their own though, whatever works for you!

 

I believe this is the best piece of advice I've read on this thread. A close second is the compressor and plug kit.