When first backing up there is a loud clunk noise?

GUNNERGARIDEL

MEMBER
2002 GMC SIERRA
6.0L
V8
2WD
AUTOMATIC
338,000 MILES

Greetings, in the last 3-4 months, I've noticed a loud clunk noise when first backing up. Let me elaborate:

This afternoon, my truck was parked at the end of my driveway but, still entirely on the concrete. I went out to my truck to run an errand. I started the engine, gave it about 30 seconds to warm-up then proceeded to back up. As I did so, I turned the steering wheel left to avoid a bush as I backed up. When I did this, I heard a loud 'Clunk', but nothing else as I continued to back up. Other than this noise, nothing else was out of the ordinary.

This is the 3rd or 4th time this has happened. I realized it was not a fluke and there must be a problem.

What are the most likely reasons for this happening? Any assistance would be appreciated.

Dudley Garidel
Baton Rouge, Louisiana

1 Reply

KEN L

MASTER CERTIFIED MECHANIC
42,959 POSTS

Can I ask where the noise is coming from, front rear, middle? Can you feel it in the steering wheel? If I had to guess I would say the U joints are going out.

Here is a guide that will help you see what the symptoms of a U joint going out will be like:

https://www.2carpros.com/articles/understanding-and-identifying-symptoms-of-a-bad-driveshaft-universal-joint

Can you please shoot a quick video with your phone so I can hear the noise? That way I can tell for sure what's going on. You can upload it here with your response. We need to hear the noise, so we know which direction to go to help you fix the car. It takes time to upload so please be patient.