Why Should You Change Your Transmission Fluid?

Fluidity of Movement

If you search “overlooked car maintenance” online, you’ll notice that nearly every list includes transmission fluid changes. Despite the transmission’s importance to vehicle performance and longevity, it’s out of sight and out of mind for most motorists – until they’re staring at a $3,000 repair bill. This post will answer the question: “Why change transmission fluid?”

AMSOIL why change transmission fluid story

Prevention is Best Practice

It’s easy to understand why. Most people direct mental energy toward things that require attention, not to things that are working properly. I bet you don’t think about your water heater or septic system much. But they demand full attention once you step into an ice-cold shower in the morning or your basement floor suddenly feels squishy.

The original equipment manufacturers (OEMs) are making it easier than ever to ignore transmission service with the popularity of “filled-for-life” transmissions and differentials today. Some OEMs don’t even include dipsticks or access plugs for checking or changing fluids. That sounds great to some motorists. “I don’t have to change or even check transmission fluid? Perfect.

Check and Change Your Fluids

If that’s not enough, the fluid must last longer than before. For example, Ford* recommends changing transmission fluid in the 2022 F-150* every 150,000 miles (240,000 km), even in severe service when towing and hauling.

Here’s where the term “filled for life” becomes misleading – and potentially expensive. It really means, “filled for the life of the warranty.” Once the warranty period ends, you can bet the dealership or OEM isn’t going to fix your “filled-for-life” transmission after it fails due to lack of maintenance.

In fact, some OEMs even direct you to change transmission fluid in these units if your driving conditions fall under the “severe” designation, which applies to most drivers. It’s vital to check and periodically change transmission fluid, even in “filled-for-life” transmissions. Nothing lasts forever, and planning ahead and performing the service on your schedule is much less expensive and disruptive than reactively fixing a broken transmission.

As you can see, with vehicles producing more power and torque, the transmission fluid has a tougher job to do. It’s vital to change transmission fluid according to the lubricant or vehicle manufacturer’s recommendations to maximize transmission life.

Signature Series Synthetic Automatic Transmission Fluid resists heat and wear in the toughest conditions, and its built-in reserve protection means it lasts for twice the OEM’s severe-service drain interval. That means you can rest assured your transmission is protected, even if service is delayed.











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AMSOIL offers a broad range of automotive and industrial lubricants and filtration equipment which exceed industry performance specifications by a wide margin. AMSOIL has also continued to set new industry standards for motor oil performance, quality and consistency. AMSOIL founder and industry pioneer Al Amatuzio built his company on the same principles that defined his career as a jet-fighter squadron commander – excellence, integrity and strong leadership. In 1972, the breakthrough came. AMSOIL 10W-40 Synthetic Motor Oil, the result of years of research and inspired by aerospace technology, became the first synthetic motor oil in the world to meet American Petroleum Institute service requirements.