I was inspecting a used car and the oil and the transmission dipstick smelled of exhaust (carbon monoxide?). What does this mean? Does it mean that the engine's gone bad and I should stay away from that car?
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What does exhaust smell on oil and transmission dipstick mean?
2 Answers
Smelling AT fluid is (or did ) give a good hint of the transmission general condition , but it requires experience. The clutches and bands have material like brake pads and if they slip, they heat very quickly although running in oil , and have a "burned" smell.
If the motor oil has a distinct smell of exhaust fumes, it might also mean that the cylinder head gasket has become leaky. Transmission fluid should never smell of exhaust gases, but can get a certain burnt smell from the clutch pads.
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Smelling AT fluid is (or did ) give a good hint of the transmission general condition , but it requires experience. The clutches and bands have material like brake pads and if they slip, they heat very quickly although running in oil , and have a "burned" smell.
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