What does it mean when the transmission dipstick has 4 markings?

[JosephineLee]

An automatic transmission dipstick has two inspection zones. The upper two markings indicate the upper and lower limits for checking when the engine is hot, while the lower two markings indicate the upper and lower limits for checking when the engine is cold. Here is some information about automotive transmission fluid: 1. Transmission fluid: Transmission fluid is a lubricant that keeps the gear system clean, ensuring the normal operation of the transmission and extending the lifespan of the transmission components. 2. Characteristics: Most transmission fluids can be used in automatic transmissions available on the market. In fact, each automatic transmission design has different technical requirements. Even the same model of transmission configured in different vehicles may have differences in torque, weight, speed, and structure. Therefore, the original manufacturer specifies its own dedicated transmission fluid. Different transmission fluids are one of the factors that affect the quality of gear shifting.

[DeMary]

When I delved deeper into automotive design, I discovered the cleverness of the four marks on the transmission dipstick. They are actually designed to accommodate oil level changes at different engine temperatures. During a cold start, the oil volume is smaller and more viscous, so there are two marks specifically indicating the minimum and maximum safe oil levels in cold conditions. After the engine warms up, the oil expands and becomes thinner, leading to two additional marks for measuring in warm conditions. If you casually check the dipstick without distinguishing between cold and warm states, it's easy to misjudge—for example, cold oil might appear to be at a high level, but only after the engine runs warm does a low-level issue become apparent. This design ensures accurate readings, preventing issues like foam leakage from overfilling or friction damage from insufficient oil. Remember to always warm up the car, park on level ground, turn off the engine and wait a few minutes, then pull out the dipstick, wipe it clean, and read the warm range. This practice helps prolong the life of your transmission.

[AdelynRose]

Having driven for over a decade, I can tell you that the four marks on the dipstick are straightforward: they help you gauge the oil level based on the engine temperature. When the engine is cold, refer to the bottom two marks, which indicate the minimum and maximum levels you shouldn't exceed. For a warm engine, check the top two marks. I always make it a habit to check the lower limit when the car is cold before heading out, and then verify the upper limit after driving for a while to warm up the engine. Don't underestimate this detail—misreading it and adding too much or too little oil can lead to premature transmission failure, which can be costly to repair. To avoid hassle, I always ensure the oil level is in the mid-to-upper range of the warm engine marks during maintenance, ensuring smooth lubrication and trouble-free operation.

[AndersonDella]

From a safety perspective, the 4 markings on the transmission dipstick are crucial as they prevent misreading and protect the equipment. The oil level changes when hot - if you forcibly use cold markings to check a warm engine, you might think there's sufficient oil when it's actually thin and inadequate, leading to overheating or gear seizure. Conversely, cold oil appears thicker with higher readings, only revealing the true level when warm. Those four points are divided into cold and hot sets of min and max lines for precision. I always warn against cutting corners - the correct method is to check within the warm range after warming up the vehicle. If you find the oil below the cold line, don't add any - wait until the vehicle is warm to reassess. Small mistakes can destroy transmissions, safety comes first.