Note! It is considered normal, if after the start of the engine, at an initial stage of transmission’s work, oil gets brown (a greenish shade) and unpleasant, but does not have a burnt smell. It is not a sign of any transmission's malfunction. Some vehicle manufacturers use different types of oil, the color of used oil may vary and might be considered as normal. In these cases, the best is to consult the professionals.
The most typical malfunctions are of torque converter, which are found while the car is in movement, when an unblocked one-way clutch is freely rotating around the axis in both directions or is fully jammed. A one-way clutch should rotate, but only in one direction. An improperly working torque converter can cause shattering, sluggish movement from start position, overheating and abnormal noises.
If in an equal monophonic sound of your vehicle, a suspicious noise is distinctly heard, it can be a consequence of malfunction in both the engine and the transmission. Non-standard sounds might not always concern the transmission and might indicate malfunctions in water pump, generator, conditioner compressor, steering column, etc.
Car proslipping might tell about the presence of automatic transmission's malfunctions that are necessary to eliminate ASAP.
In all the above-mentioned cases, it is necessary to address the vehicle to the transmission shop.Remember! The sooner you address the car to the transmission shop, when noticed any signs of malfunction, less damage will be done to your vehicle and less expensive will be the repair.