Is it OK to mix synthetic transmission fluid with regular?
Also know, can you mix different transmission fluids?
Some transmission fluids are very incompatible with different transmission types as they use different additives in the fluids. While it's not uncommon for someone to mix up which fluids should go in their car, putting the wrong transmission fluid in your car could be your vehicles fast pass to an early grave.
Similarly one may ask, is Synthetic Automatic Transmission Fluid better?
The cooler operating temperatures offered by synthetic ATFs can make a big difference to component longevity. The best automatic transmission fluids usually claim to improve vehicle fuel mileage, but renewing the fluid will almost always do that. (Here are some other ways to improve your miles per gallon.)
For your 2002 Ford application, we recommend the use of our Valvoline MaxLife Dex/Merc ATF product to meet the Mercon V specifications recommended by your manufacturer. This product is 100% compatible for mixture or replacement in your vehicle and will not void any new car warranties.