Q: can a car leak grease?

Greases are viscous semi-solids and are not used in engines or transmissions. Consequently, no grease is leaking from your engine or transmission. The greases that are used in vehicles are found in suspension joints and CV axles and those do occasionally leak. In the case of CV axle joints, when the CV boot tears, the grease will fly out as the axle turns at high speed; you will see grease all over the whee well and on the inside of the wheel. Tie end boots break, too, and the grease leaks out. If the leak you are having appears to be near the oil pan, the leaking material is either engine oil or transmission fluid or possibly both. Of course, there is a liquid in the cooling system too, that could leak down from above, so you want to be sure it is not coolant. Ethylene glycol (a typical compound in anti-freeze) can have a slight oily feel but will be distinguishable from engine oil in both color and viscosity. If you would like any leaks that you have evaluated, along with a suggested repair strategy, feel free to schedule a Leak Diagnostic with YourMechanic and a certified Mechanic will be dispatched to assist you.