BROOKSVILLE — When the tail light on Jack O’Donnell’s 2006 Cadillac broke, he requested the part from his dealer, but came up dry. After calling all the Cadillac dealers in the area, a tail light for his model was still nowhere to be found. The only replacement he could find cost about $4,000 from a private seller. "I’m afraid to drive the car now," the Brooksville retiree said. He wants to avoid any further expensive repairs.The predicament facing 77-year-old O’Donnell and collectors like him is fairly unusual. But it shows how expensive it’s become when auto aficionados have no choice but to hunt the parts aftermarket for their vehicle because the original manufacturer has stopped producing them. And depending on the part, pickings can be particularly slim.O’Donnell buys and maintains vehicles he thinks will be worth a decent sum in the future, primarily Chevrolet Camaros. The goal is to rebuild and repair them with original components to maintain the cars’ value, but when those are unavailable, he turns to a parts aftermarket.This particular tail light in a General Motors Cadillac is one of a handful of components that are relatively scarce, potentially jeopardizing the car’s value."The car is depleted in value," he said.O’Donnell’s car is a Cadillac XLR-V, "an experimental luxury roadster with a super charger on it," he said. Its specialized hard top pulls back into the trunk to become a convertible, and with 450 horsepower under the hood, "it’s an experience to drive," he said.General Motors stopped making it in 2009. O’Donnell bought the platinum-colored 2006 model — the first version of the car available — because the first release of a vehicle is often worth the most money in the future. Cadillacs are a longtime love for O’Donnell. The first time he ever saw one was when he was 8 years old, standing on a street in Miami. A man pulled up in a 1949 two-door Cadillac — black with chrome trim, swoop back, wire-spoked wheels. If you pushed on the tail light, it lifted up to reveal the gas tank."This is the most beautiful car I’ve ever seen," he remembers telling the driver."You can have one just like it," the man told him. "All you have to do is work hard.""I’ve been stuck in that situation ever since," O’Donnell said. He ran home and began mowing grass to save up for one. Related coverage: Electric, autonomous vehicles featured at Tampa auto showSince then, he’s had about a dozen Cadillacs. And he’s extremely precious about them: he never gets in his current model without towels on the seats to prevent wear, and drives it as little as possible — under 300 miles for all of last year. O’Donnell estimates that a 2006 Cadillac XLR V could sell for between $35,000 and $40,000 right now, maybe even $45,000. He hopes it will continue to climb in value in coming years.But the tail light throws its value into uncertainty because its next owner would have trouble repairing it, too.Because the car is more than 10 years out of production, parts only come from the aftermarket. There’s no set time frame for when parts for a car are taken out of production by the original manufacturer. The National Highway Traffic Safety Administration, which regulates the auto industry, does not impose any such requirements on auto manufacturers. Many times, it depends on the part. Something as vital as an airbag, for instance, is likely to be produced longer than a sun visor."The reality is that demand drives the market for replacement parts for older vehicles," Andrew Lipman, spokesperson for Cadillac, said. "As you are looking for parts for vehicles that are 10-plus years old, it can become more challenging."Collectors aren’t the only ones who need parts for their cars long after the original manufacturer stops producing them. To solve this, many manufacturers license out parts for the vehicle to third-party vendors, who continue to make the parts. Cadillac often licenses its parts out."We can without question say the vast majority of those parts are available through the independent aftermarket," Camille Sheehan, spokesperson for the Auto Care Association, said. Using such parts does not typically void a vehicle’s warranty and can often be cheaper for consumers, said Bill Hanvey, CEO of the Auto Care Association. But that’s if you can find them. Joe Lisle, parts manager at Dimmitt Cadillac, acknowledged that the tail light O’Donnell is looking for isn’t currently available."There are no dealers out there that show having this part," he said. He hasn’t received other similar complaints from customers, though. Cadillac’s Lipman said he believed the company has licensed parts out for O’Donnell’s model. Without an economic way to repair the car for now, O’Donnell must keep his fingers crossed for a cheaper part at some point."I wouldn’t sell it to one of my friends or a stranger" with the tail light so scarce, he said. "It’s like selling a gold coin that’s not real."Contact Malena Carollo at [email protected] or (727) 892-2249. Follow @malenacarollo.