The 2006 Subaru Legacy has two transmission options. The base level car comes with a five-speed manual transmission, with an optional four-speed automatic transmission available for an additional cost. The four-speed automatic transmission requires the addition of a specific type of automatic transmission fluid (ATF) for proper operation and maintenance. The manual transmission does not require ATF fluid.
Subaru recommends only four brands of automatic transmission fluid for the 2006 Legacy. The recommended brands and types include genuine Subaru automatic transmission fluid type-HP available at most Subaru dealerships; or Idemitsu ATF HP, Castrol Transmax J and Pennzoil ATF-J available at most auto parts stores.
The correct amount of automatic transmission fluid is just as important as the right type of fluid. The non-turbocharged 2006 Legacy requires 9.8 quarts of automatic transmission fluid, while the turbocharged versions require 10.4 quarts.
The automatic transmission fluid designed for the 2006 Legacy is formulated for that transmission. Using the incorrect fluid can lead to incorrect shifting and cause internal transmission damage. Overfilling the transmission can lead to excessive pressure, causing leaks or internal damage.
