Dexron-III/Mercon (D/M) does NOT meet the Mercon V (M-V) or
Dexron-VI (D-VI) rating and should NEVER be used in a transmission
that requires M-V or D-VI. However, M-V and D-VI both exceed the
D/M spec and can be used in a transmission that calls for D/M
transmission fluid. Despite this, there is really no point in using
M-V or D-VI in a transmission designed to use D/M because those
transmissions do not get any added benefit from them despite M-V
and D-VI being roughly double to triple the price of conventional
D/M.