In automatic transmission fluid, which condition would indicate worn friction materials?

In automatic transmission fluid, which condition would indicate worn friction materials?

• A. Brown, burnt-smelling fluid
• B. Clear, odorless fluid
• C. Fluid that is brown and has a burnt odor
• D. Bright tinted fluid

Answer: (C)

When friction materials in a transmission wear, clutches or bands overheat, heating the transmission fluid itself. This overheating causes the fluid to oxidize and break down, which changes its color to brown and gives it a burnt odor. So, fluid that is brown and has a burnt smell directly signals that the friction materials are worn and the system has been overheating. Clear, odorless fluid suggests no overheating, and a simple brown color or a burned odor alone wouldn’t be as definitive without the accompanying heat-related changes.

When friction materials in a transmission wear, clutches or bands overheat, heating the transmission fluid itself. This overheating causes the fluid to oxidize and break down, which changes its color to brown and gives it a burnt odor. So, fluid that is brown and has a burnt smell directly signals that the friction materials are worn and the system has been overheating. Clear, odorless fluid suggests no overheating, and a simple brown color or a burned odor alone wouldn’t be as definitive without the accompanying heat-related changes.