What is the color of transmission fluid?
Automatic transmission fluid is typically red or pink when new, and it darkens to brown as it ages. Manual transmission gear oil is usually amber to brown, with the exact hue varying by brand and formulation. Color alone is not a definitive measure of condition.
What the colors say, by transmission type
The following color cues apply to the most common types of transmissions. They help indicate whether the fluid is fresh, degraded, or contaminated—but they’re not a substitute for a proper inspection.
Automatic transmission fluid (ATF)
ATF is dyed red to help technicians spot leaks and monitor the fluid under the hood. Fresh ATF typically appears bright red or pink. Over time, it can turn brown or dark red as additives degrade or contaminants accumulate. A burnt odor or a gritty texture alongside dark color signals potential overheating or contamination.
- Fresh ATF is bright red or pink.
- Aged or degraded ATF tends toward brown or dark red.
- A burnt smell or sludgy, varnished appearance suggests overheating or contamination.
- Some brands and formulations may appear more cherry red depending on the dye, but the color norms stay in the red/pink family.
In summary, color helps flag possible issues but is not a standalone diagnostic. If the fluid looks unusually dark or smells burnt, have the transmission checked.
Manual transmission gear oil
Manual transmissions use gear oil, which is typically amber to brown. Fresh gear oil is often pale yellow to amber, and it darkens with service intervals or exposure to heat and wear. If the oil appears milky, metallic, or smells burnt, it may indicate contamination or internal issues.
- Fresh gear oil is pale yellow to amber.
- Over time it darkens to brown or black as it loses additives and accumulates wear metals.
- A milky appearance can indicate water contamination; a burnt smell suggests overheating.
- Color varies by brand and viscosity grade, but amber-to-brown is common.
As with ATF, color alone doesn’t determine whether a manual transmission needs service. Check the vehicle’s maintenance schedule and consult a technician if you notice abnormalities.
Other fluids and caveats
Some transmissions, especially CVTs or specialized heavy-duty units, use fluids that may have colorings closer to pink, purple, or amber depending on the brand. Always consult the owner’s manual for the recommended fluid type and color expectations, and rely on a combination of color, smell, and performance signals to judge condition.
Summary
Color of transmission fluid varies by type and age: ATF is typically red or pink when new and darkens with use; manual gear oil is generally amber to brown; CVT fluids often resemble ATF in color. Because color does not precisely indicate condition, check for burnt smells, viscosity, leaks, and follow manufacturer guidelines for service intervals.
What color should a transmission fluid look like?
red
Color – Most new transmission fluids should be a bright, transparent red color. Darker red or light brown is normal but reflects its age and usage. A darker brown color is an indication that fluid needs to be changed. Black is a bad sign, however.
What color is a bad transmission?
Transmission fluid discoloration and contamination often cause shifting issues and premature transmission wear. When inspecting transmission fluid from the pan, normal fluid is typically clear red or pink and free of debris. Dark brown or burnt-smelling fluid indicates overheating or wear.
What color is bad transmission fluid?
Bad transmission fluid can be black or dark brown, which often indicates overheating, or have a milky, cloudy, or muddy appearance from water or debris contamination. A pinkish, opaque, or gritty texture are also signs of a problem.
Common colors and what they mean
- Dark brown or black: This suggests the fluid is old, overheated, or oxidized. It should be changed immediately.
- Milky or cloudy: This indicates that water or coolant has contaminated the fluid, which can require a transmission rebuild.
- Bright red with metal particles: This is a sign of internal wear and requires an inspection from a mechanic.
- Pink: A pink, opaque color can mean water has infiltrated the transmission and may require a total replacement.
- Gritty texture: If the fluid feels rough or gritty, it indicates the presence of metal particles, a sign of internal wear.
- Burnt smell: In addition to a dark color, a burnt smell is a strong indicator of overheating and should prompt an immediate inspection.
What to do
- If your transmission fluid is any of the colors listed above, take your vehicle to a mechanic for immediate inspection and service.
- Driving with bad transmission fluid can cause serious problems like shifting issues and damage to the transmission itself.
- Routine checks and maintenance, including regular fluid changes, are crucial for your transmission's longevity.
What color is overheating transmission fluid?
The fluid that leaks from an overheating transmission is typically red or brownish in color but may vary depending on the make and model of your vehicle. It also has a distinct odor.
