Acura 2007 RDX Owner's Manual page 362

Automatic Transmission Fluid
FILL PLUG
5. If the level is below the lower
mark, remove the fill plug, then
add the fluid into the hole to bring
it to the level between the upper
and lower marks on the dipstick.
Pour the fluid slowly and carefully
so you do not spill any. Clean up
any spill immediately; it could
damage components in the engine
compartment.
356
Always use Honda ATF-Z1
(automatic transmission fluid). If it's
not available, you may use a
DEXRON III automatic
transmission fluid as a temporary
replacement. However, continued
use can affect the shift quality. Have
the transmission flushed and refilled
with Honda ATF-Z1 as soon as it is
convenient.
6. Insert the dipstick all the way back
into the transmission securely as
shown in the illustration.