Riverton, UT - Participants in the Goodyear/Skyjacker Extreme Rock Crawling Nationals typify knowledgeable gamblers. To casual observers, it seems they may be taking unnecessary chances as they climb walls of rock and twist their brawny vehicles around jagged boulders, but the risks are calculated.

This weekend, as the rock crawlers tackle the tough terrain outside of Reno, one of the nation's foremost gambling meccas, they will be rolling the dice in hopes for an early advantage in the severe off-roading series.

One of the primary tools some competitors will be using this year, and which promises to increase their odds of success in conquering the rocks, is Goodyear's Wrangler MT/R in a new 40-inch size, the 40x13.50R17LT. The tire is nicknamed the "Rock Spider."

Past series champion Chris Durham, last season's third-place finisher Joel Randall and legendary off-roader Walker Evans will be among the competitors using the 40-inch Rock Spiders this weekend.

"Since the Wrangler MT/R is built upon a foundation of being the most aggressive and durable off-road light truck tire in the market, we wanted to take it a step further with the most extreme size that an enthusiast can obtain," said Mark Cherveny, Goodyear's product manager for light-truck tires.

The Wrangler MT/R (maximum traction/reinforced) all-season off-road tire features a breakthrough patented Durawall sidewall construction that contains a high-tech silica compound and three polyester plies for outstanding cut-, tear- and puncture-resistance.

"The Wrangler MT/R was launched three years ago as 'the' tire for severe off-roading, and it has been a star in the rock crawling world. As we contemplated the addition of the huge 40-inch size to the product line-up, much of the urging came from these competitors and other off-roading enthusiasts who wanted an advantage against Mother Nature," Cherveny said.

"An ultra-aggressive tread and the exclusive Durawall sidewall protection combine to make the Wrangler MT/R the tire of choice among those who prefer rocks and mud, vs. a smooth highway. A tire this good is like having an ace in the hole," he said.

The Reno event kicks off the series that is operated by the Rock Crawlers Association of America (RCAA). Additional events are slated for May 22-24 in Moab, UT; July 10-12 in Cedar City, UT; and Oct. 4-11 in Farmington, NM.

RCAA President Ranch Pratt is excited about the series potential for 2003 and beyond. As the initial sponsor of the first - and most recognized - competition series for the sport of rock crawling, Goodyear has been a participant since "day one."

"Lots of groups are jumping on the rock crawling bandwagon, but our series, highlighted by Goodyear's sponsorship, was the ground-breaker and remains the real deal," Pratt said. "In the past two years, this sport and this series has been the topic of coverage by all of the leading off-road enthusiast media, along with Car & Driver, Automobile Magazine, the Los Angeles Times, The History Channel, NBC, The Outdoor Channel and many more."

For 2003 competition, the Goodyear/Skyjacker Extreme Rock Crawling Nationals will include two separate classes: Modified Stock and Super Modified. Variations between the two classes concern the hood, grill, fenders, tub/cab, hydraulic steering and the suspension.

To the uninitiated, extreme rock crawling is an unusual sport. Drivers and their spotters follow a strategy for conquering an obstacle course with lifted suspensions in the least amount of time and penalties.

Points are taken off for stopping, backing up, running over course flags and winching up boulders.