Keep an ear open for any lurching, clicking, or whirring sounds, which will all indicate an issue with the converter. Note if the sounds occur as you shift through all the gears, one after the other, including the reverse gear. Any lurches or failure in shifting gears also indicate an issue.
How can I tell if my converter is stalling?
What does a stall converter sound like?
Whining or rattling noise:
When you drive your car for a long, you should tell when something is wrong by listening to the car noise. Likewise, when a vehicle torque converter fails, the car will give a bad torque converter noise–a whining or whining sounds like a power steering pump with little or no fluid in it.
How do you drive a car with a stall converter?
Related Question How do I know if my converter is stalling?
Does a stall converter help?
Stall converters allow the car to launch in it's torque curve and get off the line much harder than a car that has much less stall.
What does a high stall converter feel like?
What precautions should be taken when stall testing?
During a stall test, make sure that no one is standing in front of or behind the vehicle. During a stall test, the torque converter's impeller is spinning at maximum speed while the turbine is held stationary.