Hendon Media Group recently did a survey of tire stores, gas
stations and police garages. We asked them how they fixed a tire with a nail in
the tread. Of these, 52 percent fixed the speed-rated flat tire in such a way
that either the speed rating was lost, which means a maximum certified speed of
The Rubber Manufacturer’s Association sets the standards for
the tire industry. The RMA leaves the tire repair policy and the resulting speed
rating up to the individual tire manufacturer. Goodyear has published a very specific
procedure to repair a speed rated tire. If the procedure is properly followed,
Goodyear is clear: The tire will retain its original speed rating. The H-rated
tires remain H-rated, and the V-rated tires remain V-rated. However, Goodyear
allows only one properly performed puncture repair for the speed rating of the
tire to be maintained.
For their part, Firestone recommends exactly the same repair
procedure. However, with an uncertain risk of internal damage caused when the
tire went flat, even when the procedure is followed, these repaired tires would
no longer maintain their speed rating. After a repair, the maximum speed would
be 85 mph, no matter what the original speed rating was.
Survey of Repair
Just because a tire company recommended repair procedure
exists does not itself justify a flat to be fixed and the tire put back into
normal police service. We contacted 26 tire repair facilities, in equal numbers
of tire retailers, service center / gas stations and police garages. The
puncture was shown or described to the tire repair centers as a nail in the
tread portion of the tire. Not a bolt, or some other large object, but a nail.
Some tire companies classify repair procedures by the size
of the damage. In this case, an ordinary nail was the problem. The puncture was
also described as being in the center of the tread, i.e., where a repair would
properly engage the belts. Most tire repair centers, but not all of them, know
that tread shoulder and sidewall repairs should never be performed.
If asked by the repair center, the tire was described as a
Goodyear Eagle RS-A, size P225/60R-16. We didn’t volunteer this information
because the staff at most tire repair places considers that a tire is a tire.
Of all the repair facilities, virtually none asked about the tire. If really
pushed for details, the tire was described as from a Ford Police Interceptor
used for patrol work. Again, this was not initially volunteered because we
didn’t want special “police” treatment. You simply cannot reliably depend on
“special police use” attention when your flat is mixed in with three dozen
other flats in the stack.
Of the two-dozen repair centers, virtually none asked for
details about the end use of the vehicle. Why would they? They are going to fix
a flat on a Crown Victoria exactly the same way they will fix a flat on a Buick
Regal, a Dodge Neon or a Toyota Camry.
At least two of the repair outfits (one garage, one general
tire retailer) knew this was a police tire since the flat was pulled out of the
trunk of a fully marked patrol car by a uniformed police officer. It is also
fair that the police garages assumed it was a repair to some kind of police
tire for some kind of police car.
Of the kinds of repair centers you and your officers are
likely to use, 40 percent said they would repair the tire with a plug. Another
12 percent said they would repair the tire with a patch. Another 4 percent said
they would repair the flat with a plug followed by a patch. Finally, 44 percent
said they would use a one-piece plug-patch combination. That means when it
comes to properly fixing the pursuit-rated tires found on virtually all police
sedans, 52 percent of these answers are wrong.
According to both Goodyear and Firestone, the tire should be
fixed in one of two ways: 1) with a plug followed by a patch or 2) with a one-piece
plug-patch combo-unit. Either way is equally valid. The repair must seal the
inner liner. A patch does this. A plug alone does not do this. The repair must
also fill the puncture. A plug does this. A patch alone does not do this.
Half of Police Garages Wrong
The police garages were
split 50-50 on the use of a plug-patch combo and a plug-only repair. That means
half of the police departments’ own garages fix a flat the wrong way.
Specifically, they fix a flat tire in a way that limits the tire to a top speed
of 85 mph. The unified word from a panel of tire specialists from Goodyear,
Continental (General), Bridgestone (Firestone) and Michelin (BFGoodrich) at a
recent Police Fleet Expo: “A plug is not a proper repair!”
The tire retailers (not counting the factory franchise
stores) are also split at 67-33. One third of the new tire retailers fix a flat
the wrong way by using a patch only. And the overwhelming majority of gas
stations and service stations, a whopping 87 percent, fix a tire the wrong way
with a plug only.
The only good news from the entire survey was that every
single factory franchise store, every one of the Goodyear and Firestone stores,
repaired the speed-rated tire the right way. “Of the tires we repair after
someone else has tried, 90 percent were repaired the first time with a plug,”
said DeAnna Paschen, Store Manager at McCord Goodyear in Lafayette, Ind.
The Right Way
Police Tires web link and Firestone’s Tire Safety web link both spell out the same,
proper procedure for the repair of speed-rated tires. This is a long and
detailed repair procedure, complete with step-by-step directions. It calls for
specific cure times and mandates that the tire was repaired from the inside, the surface was properly roughened,
the puncture and sidewall was competently visually inspected from the inside.
Of course, the puncture must be confined to the tread area only.
Unbelievably, repairs to punctures in the shoulder block of the tread and even
the sidewall are still performed by some shops.
Restrictions on the number and on the size of the repairs
must be followed. On H-rated and V-rated tires used by law enforcement, the
tires may be repaired a maximum of one time and the maximum repair diameter is
¼ inch. The tire must still have at least 2/32-inch tread depth for a repair to
The tire must be removed from the rim. No on-rim fixes are
permitted. After the removal of the object, inspect the inside of the tire for
cracks, belt separation, or fabric splitting. This is more than just an
inspection to be sure the puncture object has been fully removed from the tire.
It is a check to see that the inner surface of the sidewall has not been
scuffed and abraded too much for the tire to be used, even if the leak is
Use a pre-buff cleaner around the puncture, then a 7/32-inch
carbide cutter (for ¼-inch repairs) to clean out the puncture. Always drill
from the inside of the tire to the outside following the direction of the
puncture. Buff the liner and the plug.
Coat the tire inner liner, the plug, the patch (or the
one-piece plug-patch) with chemical vulcanizing cement, and allow the cement to
dry. Install the plug and then the patch, or the one-piece plug-patch. Install
the separate patch, or the plug-patch combo, with the tire bead in the relaxed
(non-spread) position. If a plug is to be used (as opposed to a plug-patch
combo) trim the plug 1/8-inch higher than the inner liner. In all cases, trim
the plug 1/8-inch higher than the tread surface.
The Real Solution
Based on this survey, two practical solutions present
themselves. First, and by far the best, have a “No Repair” policy for
pursuit-rated police patrol tires. This can take the form of destroying the
tire by piercing or cutting the sidewall. Or the policy can positively identify
these take-offs and designate them for non-pursuit detective and admin work.
The way most shops are run, however, the odds of this repaired tire ending up
back on a pursuit-rated patrol car are pretty good. On the other hand, are you
really ready to tell the chief that since he drives an admin car, his car gets
once-flattened tires from a pursuit car?
The second solution is to be absolutely positive the correct
tire repair is performed. Not just lip service but rigidly following the
detailed repair protocol on both the day shift and night shift. Provide the factory
documents to the repair facility and get it in writing that this procedure is
followed. This is actually possible for the routine and scheduled repair of
tires where a police department contracts exclusively with a local repair shop.
On the other hand, this is virtually impossible for nearly every other tire
repair situation. Keeping the tires repaired by two separate methods, one certified
and one dangerous, is a significant administrative liability.
Puncture is Not the
A much broader problem, a much more liability-oriented
problem than “plug versus patch” exists with repaired police tires. Just
exactly how much hidden damage was done to the sidewall when the weight of the
car slammed it between the steel rim and the pavement? Exactly how much
structural damage was done as the car was slowing down from freeway speeds with
the inside of the sidewall chaffing and abrading the inside of the sidewall?
How much internal damage can really occur without actually being visible? How
reliable are 100 percent visual inspections?
No professional tire repair facility will repair even a
pinhole in the sidewall, and yet your officer rolled the flattened sidewall
over on itself. The sidewall was pinched between the pavement and the rim edge
of a steel wheel. Gee, the pursuit car only ran with the sidewall abrading
against itself for a mile or so slowing down from 100 mph.
In the final analysis, “Is the sidewall OK?” may be a much
more serious question about repaired police tires than, “Does the repaired tire
hold air?” And, according to quality control experts, a 100 percent visual
inspection of anything (like the abraded sidewall) is only 85 percent
effective. These are some of the reasons behind Firestone’s reluctance to all
the original speed rating to be maintained.
Certified repair procedure or not, the repair to a police
pursuit tire remains both a risk management issue, and an officer safety issue.
Major departments like the California Highway Patrol and the Michigan State
Police have decided the risk is not worth the state contract price of $100 to
replace the tire. Goodyear documents indicate a properly repaired tire will
retain its speed rating. However, half of the tires are not repaired this way! Firestone
indicates the speed rating is lost for any repaired tire. At the least, consider
a “policy” of forbidding the use of repaired tires on pursuit-capable vehicles.
Jennifer Gavigan is
the Managing Editor of LAW and ORDER,
Tactical Response, Police Fleet
Manager and The Police Marksman. She can be reached at