Good morning, sir. I can't figure out what's wrong with my transmission. There is a clunking noise when I shift from park to reverse and vice versa. It just happens randomly. It just got serviced with ATF just a week ago. What could be the cause and what should I do? Thank you so much!
Hi, Poul. Aside from being a transmission problem, it could also be your constant velocity (CV) joints. The CV joints might be worn and need a new boot or even replacement of the entire part. Or it could also be your motor mounts. The motor mounts could be worn and your engine isn’t well secured to the crossmember, causing the clunking sound. Have these parts checked, too.
But if it's your transmission, it could be your parking pawl. A parking pawl is a part of your automatic transmission that locks it up. When you put your transmission into the park setting, the parking pawl is engaged. It is a pin that locks a notched wheel on the output shaft preventing it from turning.
It is best to stop the car fully before you put your vehicle into park. If you or other drivers of your car are in somewhat of a hurry and you engage the transmission into park while the car is still moving, you can damage this parking pawl. A damaged parking pawl can cause this clunking sound that you've described.
The parking pawl needs help when your car is parked at an incline. It's just a rod and if you park your car at an incline and the only thing keeping your car from rolling away is that rod, you're going to stress that part out and subject it to premature wear. It could fail or break. My suggestion is to help out your parking pawl with the emergency brake when parked at an incline.
Hope this helps you out.