Ron Hill Blog

The Automatic Transmission is still the most complex and expensive component of your car and the lubricant (OIL) does several jobs.
1. It provides the drive medium (transmits engine torque to the wheels) eg. loose the oil and the vehicle stops.
2. It prevents wear of mechanical components.
3. It provides cooling due to the circulation through the transmission and then through the heat exchanger (transmissions develop heat).
4. It contains a high detergent to keep hydraulic circuits clean and stop sludge build up.
5. It contains a complex additive package to keep an average of 200 seals soft while working in a high temperature environment and then cooling down overnight, day after day.
6. Finally it contains an anti-foam additive to prevent oil frothing up, like a bottle of coke.

Think of the oil in your car like the blood flowing through your veins – if it’s not healthy performance will suffer.

Vehicle manufacturers in their bid to win sales have adopted a “sealed for life policy” for transmissions, which works for fleet and lease buyers, but when the transmission stops outside the warranty they now cost big bucks to repair. We are talking thousands not hundreds.
Adopting a service schedule for long term ownership makes sense to me. This is as simple as a yearly fluid change and in most cases, a filter change at the same time.