Pennzoil ATF+4 automatic transmission fluid is specially formulated to meet the requirements for use as a hydraulic fluid for automatic transmissions used in passenger cars, trucks and sport utility vehicles. It is designed as a robust automatic transmission fluid with improved oxidation stability, excellent low temperature viscosity, friction durability or retention, shear stability and anti-wear performance characteristics vs. ATF+3. It's backward-compatible with Pennzoil ATF+3 and provides improved performance with temperature, anti-wear and shear stability, as well as improved oxidation and thermal stability.