Transmission fluid service

Draining and refilling transmission fluid, on whatever schedule the maker publishes — or none.

Also called: ATF change · fluid change · filled for life · lifetime fluid

What it means

Definition

Transmission fluid lubricates and, in an automatic, carries the pressure that operates the clutches. Whether it is ever changed is set per model by the manufacturer's own schedule, and the two answers can appear in the same document: Volkswagen's 2019 schedule lists the automatic transmission fluid change every 80,000 miles, and in the same line marks it not applicable for Canada, filled for life.

Why a buyer cares

What it changes

Filled for life is a schedule entry, not a property of the fluid, and the same transmission can carry a different answer in a different market. The car's own schedule is the only thing that settles it.

In practice

Where you meet it

In the owner's manual maintenance schedule, and on service records and estimates.

Two things that look alike

Not the same as

A flush machine-exchanges most of the fluid; a drain and refill leaves some behind in the converter and valve body.

Where this comes from

Sources

One manufacturer, one model year. A Ford owner's-manual interval proposed by a research agent was dropped: the URL is a session-specific viewer link that could not be verified.