* Sludge formation: The incompatible fluids will react, creating a thick, sludge-like substance that will clog oil passages and prevent proper lubrication.
* Internal damage: The incorrect lubrication will cause increased friction and wear on engine components, leading to premature failure.
* Seal damage: ATF can damage seals designed for engine oil, leading to leaks.
* Catalytic converter damage: ATF contains additives that are harmful to catalytic converters.
If you've accidentally added ATF to your engine oil, you need to have the engine oil completely drained and replaced with the correct type and grade of engine oil recommended for your vehicle. You may also need a thorough engine flush depending on the amount of ATF added. Ignoring this will likely result in costly engine repairs.
