
Transmission fluid wears out like any other fluid. Some makers say ‘lifetime’, but many mechanics still advise a change.
In this article
- Why it matters
- Intervals
- What to ask for
Why it matters
Fluid lubricates, cools and transmits pressure. Old, burnt fluid causes rough shifting and wear.
| Transmission | Typical interval | Notes |
|---|---|---|
| Conventional automatic | 60,000 to 100,000 mi | Drain and fill |
| CVT | 30,000 to 60,000 mi | Use correct fluid |
| Dual-clutch | 40,000 to 60,000 mi | Specialist job |
| Manual | 60,000 to 100,000 mi | Cheap and easy |
Intervals and costs are typical ranges. Your owner’s manual comes first.
Intervals
For automatics, 60,000 to 100,000 miles is a common recommendation. CVT and dual-clutch gearboxes often need earlier changes.
A gearbox costs more than a lot of oil changes.
What to ask for
Insist on the exact fluid the manual specifies. A drain and fill is gentler than a high-pressure flush on a high-mileage car.
Do it in this order
- Check the manual
- Use the exact fluid
- Look at fluid color
- Keep records
Practical tip
Fluid that smells burnt or looks dark brown is a sign to act. Do not ignore it, even on a ‘lifetime fill’ system.
Bottom line
Change it on schedule to avoid a four-figure repair.
Specifications, prices and rules change. Confirm current details with the manufacturer or the relevant authority before you buy or repair.



