Focus on Casings for Retread Savings

September 28, 2010

Casings are the core of your tire investment," says to Al Cohn, commercial tire technical marketing manager for Goodyear. He recommends these key practices for extracting maximum value from tire casings:

  • Maintain Pressure — Underinflated tires not only waste fuel but also overheat, which damages the casing. Check air pressures daily with a calibrated gauge. Find your tires' correct tire pressures at
  • Choose Wisely — Match tire load rating to the job. For construction duty, choose treads with stone ejectors and tire designs with extra sidewall protection. Avoid designs with a pressure distribution groove.
  • Match Duals — Both tires in a dual assembly must be properly inflated to share the load. Goodyear recommends no more than ¾-inch difference in circumference for 8.25R20 tires and a 1½-inch difference for 9.00R20 and larger tires.
  • Change Tires Early — Running tires to minimum tread depths before pulling them doesn't pay. "You want to have around 6/32 of an inch remaining to protect your casing for retreading," says Cohn.
  • Make Quality Repairs — An unlimited number of nail holes can be repaired, a maximum of two section repairs, up to a 3/8-inch injury in the tread area, and limited sidewall repairs based on stress zone.
  • Inspect Regularly — Inspections should watch for a checklist of conditions including underinflation, sidewall damage, tread damage, irregular wear, and objects embedded in tires.
Underinflating Is Overloading
(Load limits at various inflation pressures)
Carrying 6,600 pounds on an 11R24.5 tire inflated only to 85 psi is basically the same as overloading that tire by 16 percent. Goodyear's Al Cohn says it will cut tread life by 13 percent. He estimates that underinflating to only 75 psi will drop expected mileage by 30 percent.
Pressure (psi) 70 75 80 85 90 95 100 105 110 115 120
Load (lbs.) DUAL 4,660 4,870 5,070 5,260 5,510 5,675 5,840 6,005 6,205 6,405 6,610
Load (lbs.) SINGLE 4,820 5,070 5,310 5,550 5,840 6,095 6,350 6,610 6,790 6,970 7,160