The Retread Tire Association is warning of a severe shortage of retreadable truck tires, also known as casings, as the first week of July saw another round of tire price hikes.

"Whether or not you retread your tires or buy retreads, this shortage can have a negative impact on you, whether you have one truck or one thousand," says RTA Managing Director Harvey Brodsky. "Retreads act as a brake on new tire prices. Whenever there is a shortage of retreads, new tire manufacturers do not have any reason to hold back on raising their prices, and everyone who purchases truck tires feels the pain in their checkbooks."

There are a number of reasons tire makers have recently been raising prices, including volatile market conditions, supply pressures and escalating raw materials costs. Price hikes that went into effect last week include:

* Bridgestone Americas Tire Operations raised Bridgestone and Firestone truck tire prices an average of 11%.

* Toyo Tire U.S.A. Corp. increased the dealer base price list on commercial truck tires up to an average of 9% on July 5.

* Yokohama Tire Corp. raised its medium truck and commercial light truck tires effective July 1, an average of 8%.

* Continental Tire the Americas increased prices on all Continental, General and Ameri*Steel brand replacement commercial truck tires sold in the U.S. by 11%.

* Michelin North America increased prices by an average of 12% on Michelin and BFGoodrich replacement commercial truck tires. The increase also includes Michelin Retread Technologies retreads sold in the U.S.

Last month, Double Coin, Falken and Hankook raised prices.

Brodsky says truckers who are sitting on retreadable casings should either have them retreaded now, or if you don't wish to use retreads, should sell them since they will bring a higher price than ever before. "Retreaders are hungry for retreadable casings and are willing to pay a premium for popular sizes of truck tires," he says.