We recommend a transmission fluid change.
A transmission fluid change is a "drain-and-fill" method that replaces 30%–50% of the fluid and usually the transmission fluid filter, which is a safer transmission service recommended by most auto manufacturers.
A transmission flush uses a machine to remove 100% of the old fluid, including from the torque converter and cooler lines, offering a more complete cleaning. Still, it has potential risks for high-mileage transmissions that have not been regularly serviced.
Transmission Drain & Fill Fluid Change
- Process: Drain fluid via gravity from the transmission fluid pan; usually replaces ~40–50% of total fluid
- Pros: Less expensive, gentle on older transmissions, usually includes a transmission filter change
- Cons: Leaves a significant amount of old fluid in the transmission, requiring more frequent transmission fluid services
- Best for: High-mileage vehicles, vehicles that have skipped previous maintenance, or as general maintenance
Transmission Flush
- Process: A machine pushes new fluid into the transmission cooler lines while forcing old fluid out, replacing almost 100% of the transmission fluid
- Pros: Cleans out nearly all old fluid and contaminants
- Cons: More expensive, risk of dislodging debris in transmissions that have not been regularly serviced
- Best for: Regularly maintained transmissions that follow the vehicle manufacturer's recommendations
When to Choose Which Type of Transmission Fluid Maintenance
- Never flushed the transmission before? If the transmission has high mileage (+100k miles) and has never had the fluid changed, a drain-and-fill fluid change is safer.
- Regular transmission fluid changes? If standard transmission fluid maintenance intervals (every 30,000–60,000 miles) have been done, a transmission fluid flush is acceptable to keep the transmission clean.
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If you are unsure, get a transmission drain-and-fill service.