Motorists sometimes ask, “How often should I change transmission fluid?” It depends on your vehicle and driving habits. Recommended transmission fluid changes run the gamut from every 30,000 miles (48,000 km) to never. Yeah, that’s right. There is a lot of work done by the engine for your vehicle. Your car wouldn’t be able to move without the engine (obviously), which is why it is important to ensure it is clean of debris, grime, and dust. The filters will start getting blocked over time, insects find their way into the vehicle, and leaves and dirt blow under the hood. Grease covering the engine traps heat, which makes it harder for the engine to cool properly.
Original equipment manufacturer (OEM) recommendations for how often to change automatic transmission fluid cover a wide mileage range, depending on year, make and model.
Plus, if your driving habits are like most motorists and fall under the “severe” designation (towing, hauling, daily short trips less than 10 miles, etc.), many OEMs recommend changing transmission fluid more frequently.
Changing Engine Oil Can Make a Lot of Difference
They’re supposed to last the life of the vehicle, but what do you suppose will happen if the transmission fails once the warranty expires? You’re going to get stuck with a hefty repair bill, that’s what. Be proactive and change fluid at least once during its lifetime.
Follow the recommendations in your owner’s manual.
But, how many of us dutifully follow them down to the mile? Many motorists completely forget about their transmission until it begins to shift hard, jerk or hesitate. Out of sight, out of mind, right?
Not good, especially if you tow or haul.
Heat Kills Transmissions
Over time, transmission fluid oxidizes (chemically breaks down). High heat generated from towing and hauling speeds the process.
Fluid that has broken down can cause sludge and varnish to form, which clogs narrow oil passages and contributes to clutch glazing. Soon, your vehicle can begin to shift poorly.
In these cases, wouldn’t it be great to use a transmission fluid formulated with reserve protection against heat in case life gets in the way of recommended maintenance?
Symptoms Of Low Transmission Fluid
It’s not just heat that leads to poor shifting. Low transmission fluid can also present a number of problems, including…
- Inconsistent, jerky shifts
- Hesitation
- Surging
- Increased transmission temperatures
source : https://blog.amsoil.com/how-often-should-i-change-transmission-fluid/