Community Forums

Traildust · 07-31-2015, 03:33 PM

My neighbor has a 5ver with the spare tire mounted on the rear bumper via a spare tire rack clamped to the bumper. He showed me the damage it did after it apparently exploded on it's own the other day. The top third of the tire seperated from the rim and went up right into the back window.It shaddered the window and put a big black skid mark on the fiberglass back wall. He was working in his yard when it happened and said he heard it blow but didn't know what had happened till later. I have to admit I have never heard of this happening anywhere else. He said he thought it probably had 70 to 80 psi air in it. The day that it happened was not that hot for this area but was in the low 90's.
Bill

Skip426 · 07-31-2015, 05:40 PM

Any idea how old the tire was?
Many years sitting with the exact same spot exposed to the sun , Murphy says, anything that can go wrong , will.
See the same thing every year when we get south, trailers stored on site at the park will have blown tires, on those that are exposed.
Temp. in the park today 107.

Traildust · 07-31-2015, 06:10 PM

He's only had the Trailer about two years and does use it several times a year. He did say it was the original spare that came with the Trailer. My spare is mounted underneath the Trailer wonder what would happen if it decided to blow?
Bill

Skip426 · 07-31-2015, 06:46 PM

Was the trailer new when he got it?

Spare tire on my 2000 Dodge P/U was original and spent 12 years at max inflation ( 80 psi.) riding around under the truck, while I still had it . Probably still there. Tires on the road were replaced 4 times.
Under-slung spare on my 2005 5er, was still in place after 7 years when I traded it off. Again inflated to max.

JIMNLIN · 07-31-2015, 07:37 PM

What happened to your neighbors spare tire happens more than you would think. I've noticed other RV folks report spare tires letting go at home and at the campgrounds/RV parks.

We were in a KOA one October enjoying the cool mountain air near Chama, NM. The wife and I had just sat down for a samwinch when ....BOOM. It actuall shook the trailer. Well the first thing I thought was a LP tank went off. Ran out the door and found other campers near me looking in all directions for smoke or fire. Nothing but a bit of dust moving away.
About a hour later a guy knocked on the door and says this Skyline tire cover may be mine as I had the only Skyline trailer in the park.
Checked the spare hanging on the rear bumper and sure enough the cover was missing. Found a 10" long zipper in the tires sidewall next to the tread. The guy says he heard the blast and was looking out the window when the cover sailed into the street like a frisbee.
His trailer was behind me one lane and 4 spots down.

This was in 1984. The tire was on a new 26' 5th wheel Aljo by Skyline and was less than a year old...and never on the ground. The tire was a bis ply ST H78-15 8 ply rated tire from Firestone. Radial ST tires hadn't hit the streets then.

kgburns1 · 08-01-2015, 02:22 AM

Oddly enough, the spare tire on my Coachmen just exploded last week. The tire was 3 years old and had never been on the ground. It had 65 PSI in it when I checked it last month and had a vinyl cover over it.
I don't know exactly when it exploded, I just happened to look out the garage window and saw that the over was ripped and torn, so I checked it out.
The fifth wheel was backed in close to the north side of the garage, so it stays in shade until well up into the afternoon.
Now I'm worried about how safe the other four tires are.

wa8yxm · 08-01-2015, 06:45 AM

One of the more interesting things about tires is they really do not like sunlight.. Now if a tire is in service (Meaning mounted and rollign, rolling, rolling, down the highway) then the flexing of the side walls and tread bring essential oils to the surface that act somewhat like a sun screen and protect the tire.

But if it's mounted on a spare tire rack, EVEN IF IT IS COVERED, (most covers) UV light is free to play.. Many spare tire covers UV goes through 'em like an open window. The tire ages and cracks and .. Well,,, BANG happened.

That said. I suspect a defective tire.

A spare under the RV or in the trunk of a car or covered with a METAL cover does not get as much sunlight (if any) and thus lasts longer.

FastEagle · 08-01-2015, 12:33 PM

IMO, and remember that this is just my opinion. Tires that are stored in a vertical position and exposed to the sun light seem to be the ones most often reported to suffer sudden explosions. Those that are mounted horizontally under a trailer frame don’t seem to suffer from such damage. Almost always the exploded tire has never been used or even had any weight placed on it. My conclusion is - and especially with ST tires - the chemical compounds used in the tire’s construction were never activated by usage and they settle into one place and may even boil to the top causing the tire’s cords to rot until the construction is no longer strong enough to support the inflation pressure loads….BOOMB!

partsman01 · 08-02-2015, 02:55 PM

Spare tire mounted in front of rad on my old ford truck let go one day, it actually kept air in it, but the tread portion and some of the cords ripped open and made a bit of a noise, so they will fail eventually.