How Does Transmission Fluid Break Down?

Posted Posted by AAMCO Colorado in Blog, Colorado Automotive Advice, Transmission     Comments No comments

AAMCO Transmission RepairAnybody who drives a car needs to get a transmission service regularly to flush the transmission fluid because over time and with use, the fluid breaks down and eventually becomes unsafe to drive.

Any burning smells, stuck gears or slipper gears, grinding gears, shaking cars, clunking, or dripping puddles may mean the transmission fluid is past its prime and needs replacing since it is old and has broken down.

How does transmission fluid break down though?

The Purpose of Transmission Fluid

In order to understand how transmission fluid breaks down, it’s important to know what its purpose is in the first place.

Transmission fluid acts as a lubrication for the hundreds of moving parts present in a transmission. The fluid moves through the various seals, gaskets, and gears to reduce friction, keep things from overheating by cooling the transmission.

What Happens to the Transmission Fluid Over Time

While the transmission fluid moves across all the parts, it is natural that tiny pieces of each material breaks off, much like a river running through a field and gradually pulling away pieces of dirt and rock with it. The fluid is then less effective at cooling the transmission. As more heat is present, it breaks down the fluid and thickens it up.

The thicker transmission fluid struggles to go through the filter and there’s less fluid to lubricate the transmission. The seals and gaskets won’t get the fluid pressure it needs and also break down, leading to leaks and cracks. In addition, the gears receive less lubrication and create more friction and more heat.

In the end, there is a buildup of debris and sediments in the transmission fluid that needs flushing.

Frequency of Transmission Services

Since the breakdown of transmission fluid is inevitable, taking your car in for a transmission service for a flush is critical to extending the life of your car. Depending on how much you drive, if you tow things often, or can’t even remember the last time you had a transmission service, people should often get theirs flushed once every two years. If you ride your car harder, then be sure to take it in every year.

Another thing to consider is if you drive city roads mostly, then you shift your gears more frequently and generate heat more often compared to highway driving, unless you are commonly in stop-in-go rush hour.

Either way, getting a transmission diagnostic every couple of years will allow an expert mechanic to inspect your transmission fluid and swap it out without worry of a huge surprise transmission repair down the road.

If you need to get your transmission fluid checked, Trust in AAMCO Colorado. We have over 50 years of experience servicing and repairing transmissions. Schedule an Appointment with one of our friendly AAMCO Locations near you today.



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