Ultra1Plus ATF Dexron III/Mercon Multi-Purpose, 1 qt.

A: Thank you for your thoughtful questions! I’d be happy to clarify the points you raised. 1. Compatibility Between Dexron III and Mercon: While Dexron III was developed as a General Motors (GM) product and Mercon as a Ford product, they were formulated with similar specifications during their production years. This similarity allowed for many automatic transmission fluids (ATFs) to meet the requirements of both standards, leading manufacturers to label such fluids as “Dexron III/Mercon compatible.” However, this compatibility is based on performance standards, not on the original licensing by GM or Ford. 2. Manufacturer Specifications: You are correct that each manufacturer develops specifications to optimize vehicle performance. Over time, these specifications have evolved, with newer generations of ATF fluids offering improved performance, compatibility, and efficiency for modern transmissions. However, some vehicles—especially older equipment—still require specific fluids, like Dexron III, per their owner’s manual. 3. Discontinuation of Dexron III in 2005: Dexron III was discontinued in 2005 when General Motors introduced Dexron VI, which offers superior performance and is backward compatible with older GM transmissions. However, because many vehicles and equipment still require Dexron III based on their original specifications, we continue to manufacture Dexron III to meet this demand. These fluids are formulated to meet the original Dexron III specifications, providing a reliable solution for those who need it. 4. Why Aftermarket Fluids Are Labeled Compatible: Many aftermarket manufacturers continue to produce “Dexron III/Mercon-compatible” fluids for the aftermarket market. These fluids are designed to meet the performance characteristics of both standards but are not licensed by GM or Ford. It is critical to consult the owner’s manual to ensure the proper fluid is used, especially for older vehicles and equipment. Summary: While Dexron III and Mercon were created for different manufacturers, their overlapping performance characteristics allowed for compatibility in some applications. Despite the discontinuation of GM-licensed Dexron III in 2005, we continue to manufacture Dexron III to serve the needs of customers whose vehicles and equipment require this specific fluid, as outlined in their owner’s manuals.