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Clunk Sound in Rear when in Reverse?

VWGTI123

2012 PW #2558
124
0
Car has been sitting in the garage about 2 1/2 weeks. So I start her up and go to pull out of the garage and when I depress clutch put in reverse and start to back out.... hear a clunking sound from the rear... immediately depressed clutch again.. put in neutral, waited about 20 sec and tried again, this time no issue. Once on the road.. no issue.

Has anyone else experienced this? Car only has 598 miles on it and has been babied.... never did it prior today. ?? What could have caused this???
 

Sesshomurai

The clunking was in lock step with the wheels turning? How many clunks and did it come from one side or the other?

In a garage, sound can deflect easily and fool you as to what direction it originated.
 

VWGTI123

2012 PW #2558
124
0
darreng505 said:
The clunking was in lock step with the wheels turning? How many clunks and did it come from one side or the other?

In a garage, sound can deflect easily and fool you as to what direction it originated.

What is Lock Step? sound started as soon as i started to lift the clutch and car started to back up. Like the differential/gears were grinding. Definately was from the rear wheels and not the tranny. Could not tell what side.. I had driver window open so could have come from either wheel. Very Strange and alittle alarming. I do leave the car in first gear when parked in the garage.. and I def know the e-brake was down.
 

Sesshomurai

Just thinking out loud. Only parts that rotate with the wheels in the rear are the differential and axles (disclaimer: I'm no mechanic). Or maybe axle/driveshaft needs grease?

What I meant by lock step is that the clunks were spaced equally apart as the wheels rotate (e.g. 1 clunk per revolution). Or was it a lot of clunks before the wheels rotate once?

Although I never heard of this, since it sat for 2.5 weeks, I wonder if the fluids settled completely (e.g. in the diff) and played a role in it, but I doubt it. Prolly should take it in and have the dealer double check the rear (fluid levels, grease, etc).
 

VWGTI123

2012 PW #2558
124
0
It was only one clunk as the car started to roll... and that is when I immediately stopped depressed clutch applied brake and went to neutral. Then I waitied few moments and repeated the process.. but this time with no issue. It is like the rear end was stuck/locked in the a bad gear or something. IDK... I will monitor and hope it does not happen again. If it does... right into the shop she goes. I hope it was just an anomaly. Thanks for your feedback. Wanted to see if this happened to any other Boss owners.
 

Sesshomurai

Brake pads could have just been stuck to the rotors maybe. But yeah, if it happens again, take'er in.
 

ace72ace

Zaino, I put that $hit on everything
1,242
71
Could it have been a driveshaft clunk on one of the u-joints? When the sound occurred was the drivetrain shifting load from neutral ? These 2 piece drive shafts will sometimes clunk. I had noticed at least 3 in my own driveway before installing my DriveShaftShop aluminum shaft. Not another clunk since the swap.
 

VWGTI123

2012 PW #2558
124
0
ace72ace said:
Could it have been a driveshaft clunk on one of the u-joints? When the sound occurred was the drivetrain shifting load from neutral ? These 2 piece drive shafts will sometimes clunk. I had noticed at least 3 in my own driveway before installing my DriveShaftShop aluminum shaft. Not another clunk since the swap.

Not sure.. I guess it could have been... In all my manual cars.. I always depress clutch, put in neutral then first then in reverse.. never straight to reverse. This felt like the back wheels/diff were locked. Don't know if you ever blew a rear-end, but felt/sounded alarmingly similar. I guess the good thing in all of this, is that I took the car out, went to a few stores, used reverse few times and no issue. Felt like she always does. No odd smells, checked for leaks, all good. Will just have to monitor. The last time I drove the car was washing it then put in the garage.. hope as darreng505 stated, the brake pads may have just stuck. Thanks for all the feedback. Appreciate it.
 
I would go with the pads stuck to a rotor. Never happened on my BOSS but I have had it happen on other vehicles. Usually when I parked the vehicle after brakes were hot or after car was washed and sat for a day or two before being driven. Unless it happens on a regular basis I would not be concerned.
 

Justin

Save the dawn for your dishes!!!
My guess is the driveshaft made the clunk and if you had the parking brake set the pads were still sticking to the rotors a little and held the car just a tiny bit.
 

PeteInCT

#LS-378 - So many Porsche's, so little time....
Moderator
2,848
14
Connecticut
darreng505 said:
Brake pads could have just been stuck to the rotors maybe. But yeah, if it happens again, take'er in.

+1, especially if you have high metal content rear pads....
 

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