I think I found the lifespan of the OEM bulbs on my Buick. At approximately 12 years of moderate use, it's not a bad run for them. I've replaced all the brake lights, the rear marker lights, and both front side marker lights. They all died within a few months of each other. The side marker lights died within a week of each other. Thinking about it, the only bulbs I haven't replaced are the interior lights and the front turn signal bulbs.
Many of the hard to reach bulbs were replaced with long-life replacements. Hopefully those will be good for another 12 years.
Many of the hard to reach bulbs were replaced with long-life replacements. Hopefully those will be good for another 12 years.