Scared of inflating old tires?

A few years ago, a friend of mine had the spare on the back of his van blow out just sitting there on a warm day. Ever since then, I'm extra-jumpy about old tires.

Forget driving on them significantly, but how much should I worry about re-airing the old, poorly-seated tires on the Ranchero as it sits in the shop? They go flat every couple of weeks, and depending on how stressed I am on any given day, I'm pretty sure I've put on a face shield and earmuffs just to air it back up so it wasn't sitting wonky.

Am I being completely paranoid? It's going to need new tires and wheels to fit under the un-hacked quarter panels, so I could just do that, but it's sort of out of order, I'd rather not subject the new wheels/tires to shop wear unnecessarily, and then there's just the feeling that it's a ridiculous concern.

What says the hive?

Yes, I am scared of inflating old tires.

How old are they? Do they show signs of dry rot/cracking? If 10+ and dry rotted, then yeah, I'd probably dump them now.

I don't worry about it too much, but I also don't air them up a lot. 15-20 pounds is plenty for something sitting around the yard on crappy tires.

Yeah, you really don't need to put much air in them just to get it to roll. 10psi is more than halfway to 35psi when it comes to how hard the car is to push/roll.

Reminds me of when I bought the M5 7 years ago and checked the date on the spare(well used I will add). it was made in 1992. I bought 5 new matching tires shortly thereafter.

I worked in a used tire shop in high school. We aired up tons of old crappy tires. Only a few blew. No one ever got hurt, but we did jump. We would always seat the beads at 80psi so when they blew, there was force. I wouldn't worry too much.

In reply to mw:

I had a tire explode 8 feet from me at "only" 30psi once. Sidewall just unzipped when inflating it.

That was enough of a lesson for me!

Should see what happens when a split rim truck tire separates at around 125 psi. We were doing controled tests to failure as part of a testing program. The force that is released is something else.

Fear is basically what prompted me to finally replace the tires on my Chevy duallie. The tires had plenty of tread, but were getting near 20 years old and started showing some deterioration on the sidewalls. I was not a fan of getting down there with my head next to the tire and inflating them.

Plenty of scary videos on Youtube for anyone who cares to look. For me, it's pretty much only the super obvious sidewall bubbles that get me a little nervous. There have been tires i deflated on the car before i took them off and set them on the ground. I knew they drove in like that, but still..

I blew up a bicycle tire as a kid. Don't even think I had a gauge, just grabbed the air hose at the gas station and whoosh. Till whoosh became a loud bang, and I swear I saw a flash. Still jumpy airing tires up to this day.

Jerry wrote: I blew up a bicycle tire as a kid. Don't even think I had a gauge, just grabbed the air hose at the gas station and whoosh. Till whoosh became a loud bang, and I swear I saw a flash. Still jumpy airing tires up to this day.

Had a tire blow off at the bike shop once, just out of the blue.

Tires are easy to get to blow off, either if the tube gets pinched between the tire and rim, or mostly if the bead isn't seated properly on the rim, especially with the thrice-damned lipless Schwinn fractional-size tires that will NOT hold a seat until you have enough air in them to hold a seat.

But this was just a quiet day, and a bike we hadn't touched for two days calmly blew a tire off the rim. Talk about your "slow cookoff"!

I ran a set of 30+ year old polyglass tires for a summer, would run another set if i could find them cheap enough and still intact!

In reply to dean1484:

Split rims are dangerous as hell. OSHA requires a cage be available for aircraft tires because a) split rims and b) they will kill you if they come apart when inflating.

We had a giant double walled quarter inch thick per wall steel cage for inflating rebuilt wheel assemblies at my last job. I insisted that my guys use it when they did that work... And I actually got pushback on it

I'm probably more lax than I should be with car tires but if they're seriously rotted just enough to get it to roll is the rule of thumb.

In reply to The0retical: I have seen the results as we're testing for lawsuit related reasons. Grusum stuff. We tested them in a cadge made of 2" chrome molly steel tube steel. And it managed to dent/bend them a good 3-4 inches.

The cage we were required to have in order to be qualified to work on Goodyear run-flat tires in 1997 had 4" tubes about a foot apart.

I've seen YouTube videos of those cages being deformed by tire explosions...

Its not tires, its split rims that make me run. berkeley that noise, man.

In reply to dean1484:

We had these for rebuilds:

It's still no joke when one goes off in there. The Air Force actually has regulations on the square footage of the shop the rebuild work may be accomplished in, as the concussion from a wheel coming apart will do a ton of damage to both your body and hearing, even if it's contained.

I actually had it out with one of my bosses at one point when we were servicing assemblies at a remote location. I found out that the wheel half bolts were being reused during the rebuilds.

On the list of things I want to put my face near, wheel halves which multi ton aircraft have been stressing over and over again several hundred times is close to the bottom. Especially when I'm doing work in the middle of nowhere. There's a reason the hardware is classified as single use.

I had pneumatic wheels on a work cart. I was doing a large job in the Post Office distribution center here in town. Out of the blue, one of those tires exploded and sounded exactly like a gun shot. Every employee in the place hit the floor. Security came running, guns drawn.

For some reason they wouldn't allow me to bring that cart back into the building.

I did some maths, just for curiousity sake. I used A 28x7 tire on a 15x5.5 wheel inflated to 15 psi as my reference. This isnt completely accurate because in my model the sidewalls, tread and rim are flat and square because it made the figuring easier. Anyway i came up with 1752 sq. in. of surface area inside the tire, counting the rim. At 15 psi, that gets you to total of 26,280 pounds of force. Bump the pressure to 45 psi and that gets you to 78,842 pounds.

Ive never had one burst while inflating, but when we drug the packard out of the barn after its 47 year slumber we hooked up a hose to the tires that let us inflate them from a distance.

Ransom wrote: A few years ago, a friend of mine had the spare on the back of his van blow out just sitting there on a warm day. Ever since then, I'm extra-jumpy about old tires. Forget driving on them significantly, but how much should I worry about re-airing the old, poorly-seated tires on the Ranchero as it sits in the shop? They go flat every couple of weeks, and depending on how stressed I am on any given day, I'm pretty sure I've put on a face shield and earmuffs just to air it back up so it wasn't sitting wonky. Am I being completely paranoid? It's going to need new tires and wheels to fit under the un-hacked quarter panels, so I could just do that, but it's sort of out of order, I'd rather not subject the new wheels/tires to shop wear unnecessarily, and then there's just the feeling that it's a ridiculous concern. What says the hive?

Well...the worse thing that could happen if you wear your face shield and earmuffs and don't need them is....not much. Sweaty ears maybe. The other side of the coin is much worse.

Maybe i should have mentioned about the youtube videos.. I think there are many where the person in the video ends up dying and they leave it up to your ignorance to not figure that out. So if you don't like watching people get fatal injuries, maybe veer away.