Happened to the Spare Tire?
No, not the
one around your middle. The one that used to be in your cars
Most cars (note:
passenger cars, not just big trucks and SUVs) used to come with
a full-sized spare tire.
to them? And why?
Two thing led
to the near-abandonment of the once-common full-size spare tire:
got smaller. A 1973 Nova considered a compact
when it was new would be classified as at least a mid-sized,
if not full-sized car, by modern car standards. Todays
compact is a car like the Toyota Corolla a much smaller car,
overall. And it has a much smaller trunk. A full-size spare would
eat up most of the available space, which is the main reason why
cars like the Corolla dont come with full-size spares anymore.
cars today have fairly small trunks by the standards of what was
commonplace a few decades ago.
wheels and tires have gotten a lot bigger. Taller and wider. Seventeen
and eighteen inch wheels are commonplace on current-year mid-sized
family sedans. Even economy cars usually have at least 16 inch wheels.
Taller and wider wheels (and the larger tires that mount
on them) take up more space than the once-typical 15×7 (or
smaller) wheel/tire combos of the past.
So, as a purely
practical matter, the full-size spare outgrew its environment. Who
wants to cart around a fifth wheel/tire that takes up a third to
half the available trunk space?
was is changing styles. Many new cars (crossovers
and hatchbacks) dont even have trunks, properly speaking.
They have cargo areas. Now youve got the additional
issue of visibility. No one wants to see a big old tire laying on
the floor of their cargo area.
So the car
companies (or the tire companies) came up with the mini
or space saver temporary spare tire.
used a steel rim that was the same diameter (and sometimes even
width) as the four regular wheels but the tire itself was
deflated (and hence very compact). Cannisters of compressed carbon
dioxide (or similar) came with the space saver and were used to
inflate the tire when it was needed. The upside was these spares
took up less room when not in use and also weighed a lot
less than a standard-size spare, which helps both fuel economy and
handling. But this this type of temporary spare isnt used
much anymore, probably because of the hassle of having to inflate
the tire and also because it wasnt uncommon for the inflator
to have leaked d(or been lost) leaving you stuck and outta luck.
mini spares replaced the inflatable space saver; these are like
the original space savers except the tire doesnt require inflation
prior to installation.
As with the
earlier inflatable type, current minis are great in the sense that
they free up valuable trunk space, but have the downside of not
being an equivalent wheel/tire relative to your other three still-good
ones. The mini wheel will usually be much narrower, especially compared
to the now-typical eight and nine inch wide alloy wheels many new
cars come equipped with. Also the tire itself will not be high-speed-rated
(as many new car tires are) or have the same ratings for load and
heat and so on.
And here we
come to the biggest weakness of these space-saving mini-spares:
Theyre designed to get you to the next service station
and thats it.
Most have warning
stickers on them that caution against driving for more than about
50 miles or so or exceeding 50 mph. Expect your cars
handling (and braking) to be affected not for the better.
The good news
is you may never need to deal with this. Flats are not as common
as they used to be because tires are tougher than they used to be.
Theres still the potential for physical damage (running over
a nail, etc.) but many people drive for years and years without
getting a flat.
to breaking out the space-saver mini if you do have a flat is a
can of emergency tire sealer/inflator such as Fix-a-Flat (or equivalent).
Unless the tires sidewall has been flayed open, or you have
a really massive hole in the tread, this stuff will usually get
you going much faster (and more safely) than jacking up the car
using the usually pitiful factory-provided jack/tools and trying
to install the mini by the side of a busy road. Just screw the inflater
bottle onto the tire stem and press the button. Usually, thats
all there is to it. Maybe a 5 minute stop and you are back on the
road and without your hands and clothes covered in grime
and your (formerly) clean cargo area mussed up by your nasty old
A few things
to know, though: Like using the mini, using Fix-a-Flat is not a
permanent fix. You should have the damaged tire dismounted and properly
repaired as soon as possible. While handling/braking performance
will not noticeably deteriorate (because youve still got the
factory-type wheel/tire mounted instead of the much-smaller, less-capable
mini) the tires structure could be compromised, so dont
drive super fast or super hard. Also, tell the tire place you used
the sealer. The goo inside the tire can be a hazard during dismounting
if the tech doesnt take precautions and if you dont
tell him, he may not.
is to buy a real-deal spare in the same size (and with the same
type tire) as the other four. If you have a car with a big enough
trunk or dont mind losing the trunk space this
alternative eliminates the problems of the mini and also the emergency
Be sure that
the spare wheel you get is correct; i.e., that it has the right
bolt pattern, diameter, width and backspacing for your
vehicle. The best way to assure this is to get a a spare thats
the same type of wheel as the ones that came on your car (junkyards
are a great place to find these) and then mount a tire on it thats
the same size/type as the tires on the other four wheels.
with permission from EricPetersAutos.com.
[send him mail] is an
automotive columnist and author of Automotive
Atrocities and Road Hogs (2011). Visit his
© 2011 Eric Peters
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