I've been buying from the team at Lincoln Diesel for about 12 years now and the service is always top notch. The team there is knowledgeable and is one of the reasons my '01 Duramax Silverado is still running strong at 1.4 million miles. I also really like that not only do they sell the performance parts and upgrades but they have a deep inventory of OEM AC Delco and GM parts for us stock drivers.