Dear Doctor: I was at the repair shop with my Hyundai for routine service and the technician said the transmission fluid needed to be changed. I said go ahead and change it. He said he had to get the fluid from the Hyundai dealer. I thought all transmission fluids were the same. He said Hyundai uses a special fluid — and also costs more than regular transmission fluid. Is this true? Barry
Dear Barry: You have a very good technician. He is 100 percent correct. Automotive manufacturers have their own specifications for transmission fluids, and some even for the final drive fluids. There are some universal fluids for multiple vehicles, including coolant. There are major differences in transmission fluids and not just the color of the fluid. As for coolant, there are a few different vehicles that I recommend the factory antifreeze coolant. I do not recommend mixing these fluids.