Humans Can Tame Roadside Alligators

Despite advances in tire technology, tire debris still lines the nation's highways and the problem is actually getting worse. In many places particularly during summer weather, those unsightly strips of tread and steel belts (alligators) are so plentiful they have become a public safety issue. From surveys of tire debris in 1995 and again 3 years later, a task force of The Maintenance Council (TMC) counted 28% more alligators from the same 13 locations in 1998. The total count in 1998 was 2,200 tires.  In the latter survey, most of the tires were retreads and 70% of them were rib-type tires, which points to trailer and dolly positions. It's easy to see why public safety advocates are quick to point the finger at retreading as the culprit and call for government controls of retreads usage.  The truth, again borne out by TMC study, is that neither manufacturer defects or retreading is at fault in the overwhelming majority of tire failures on the highway. The true culprit in almost 90% of the cases is underinflaton due to poor maintenance, and to a lesser degree, road hazards.  Here are some specifics from the most recent survey:  59% of pieces inspected had failed due to belt separation and other mechanical problems.  27% had failed due to road hazards, such as nails or rock penetration.  Only 6% failed as a result of tire repairs. Clearly the cost of running underinflated (or overloaded) tires, retread or new, is very high. A recent TMC survey of commercial truck fleets showed the average out of pocket cost of each tire related road problem is $180.00 plus the replacement tire. The average down time is more than 2.5 hours and the average cost of driver delay time is $130.  That's only the start of your woes. Add to these problems the cash costs a missed delivery (especially just-in-time) and loss of future business opportunities. Is the problem industry wide? The TMC survey of fleets revealed that 60% of the fleets had more than 11 road calls each month.  Though most tire failures involved retreads, simply switching your replacement program to all new tires would be an unnecessary and expensive move. Recycling a $75. casing one or more times with retreads not only delays tire disposal costs, which can be $3 to $7 per unit, but saves big time in replacement costs, as much as 38%, surveys show.  The TMC surveys have shown that underinflation is the most frequent cause of tires "giving in" along the highways. And the fact most were on the trailer axles indicates a weak spot in maintenance and driver attention to trailer tires, which are more often overlooked during inspections than tractor tires.  Sometimes fleet mechanics don't see their company trailers for weeks and even months.  The other pertinent issue is driving technique; how careful drivers are to avoid road hazards, curb damage or too much pedal on the metal. A loss of inflation pressure through penetrations or impact and excessive speeding both create heat buildup in tire casing, leading to fatigue and eventual failure. In the end. belt package and tread detach themselves from the tire body.  Most fleets (80% of those surveyed) assign tire responsibility to their mechanics and about 2/3rds of them have written tire maintenance procedures. At least 97% use pressure gauges to check tires.  But is that enough? Apparently not. Only 22% of their drivers check the psi before starting a trip and of those, just 37% use an air pressure gauge, calibrated or not. The survey also showed 1/2 of the drivers didn't think checking air pressure was their job.  Drivers are key players in preventing tire failures. Through driver education programs, thy must be made aware of their tires importance and what can happen when they fail to check tires (tractor AND trailer) before and during trips. A TMC brochure sent to fleets during 1999 states checking and adjusting tire inflation pressure on 18 wheelers takes only 20 minutes. For the driver's own safety, that could be the shortest 20 minutes he or she will ever spend.  DRIVER'S CHECKLIST FOR KEEPING TIRES INFLATED:  Use calibrated air gauge  Inflate to specified pressure  Have tire removed if 20 psi under target  Are metal valve caps on tight?  See any tire damage or nail penetrations?  Don't forget inside duals. Download PDF version from Commercial Tire Management.  Download PDF (2.4 MB) This article originally appeared in COMMERCIAL TIRE MANAGEMENT, a Goodyear Tire & Rubber Company publication. Reprinted with permission.

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