2010 Ford Mustang Owner's Manual - Page 290

Maintenance and Specifications The fluid level will drop slowly as the brakes wear, and will rise when the brake components are replaced. Fluid levels between the MIN and MAX lines are within the normal operating range; there is no need to add fluid. If the fluid levels are outside of the normal operating range, the performance of the system could be compromised; seek service from your authorized dealer immediately. TRANSMISSION FLUID Checking automatic transmission fluid The 5R55S transmission does not have a transmission fluid dipstick. Refer to your scheduled maintenance information for scheduled intervals for fluid checks and changes. Your transmission does not consume fluid. However, the fluid level should be checked if the transmission is not working properly, i.e., if the transmission slips or shifts slowly or if you notice some sign of fluid leakage. Transmission fluid should be checked and, if required, fluid should be added by an authorized dealer. Before adding any fluid, make sure the correct type is used. Use only MERCON V automatic transmission fluid. The type of fluid used is indicated on the transmission fluid pan, extension housing. Refer to Maintenance product specifications and capacities in this chapter. Use of a non-approved automatic transmission fluid may cause internal transmission component damage and void the warranty. Do not use supplemental transmission fluid additives, treatments or cleaning agents. The use of these materials may affect transmission operation and result in damage to internal transmission components. 290