Significant wear can develop on the low and reverse clutch preventing the park pawl from engaging. This can prevent a "no park" condition to occur while the engine is running, causing unintentional movement of the vehicle without operator action. (the "no park" condition will not occur while the engine is off.)
Dealers will check the transmission fluid for contamination which will indicate if the low or reverse clutch is worn. If the transmission fluid shows contamination, the transmission will be replaced.
