I've been noticing that, sometimes when I put my car in reverse and backup 10 feet or so, that there's a thump that comes from the rear end. It sounds exactly like I'm backing up over a seam or crack in the pavement, but there's no seam. This isn't a clunk or shock - just a mild, dull, short, thudding sound.

Does anybody know what this might be? In terms of "what's changed" on the vehicle, I did upgrade to the Sport suspension last December. I don't know whether or not this behavior existed prior to then. I've only started noticing it within the last 3 months. Otherwise, everything in the car (brakes, suspension, transmission) seems to work just fine. This only occurs when I put the car in reverse and then within the first 5-10 feet of going backwards. If I try to repeat the behavior (by putting the car in drive, pulling forward, then back into reverse and pulling backwards) I cannot - it just seems to happen once and then not again until after I've put some miles on it and then put it into Reverse again. It also doesn't happen everytime I put it in Reverse - only occasionally.

Any ideas?


-townsley-
2003.0 Premium BS/Willow 5AT Sedan
ZTube/K&N Filter/Sport Suspension
Grounded/Tinted/Splash Guards
Lip spoiler/Aluminum Pedals
Battery Disconnect Switch

 

Does it happen right after you start the car? It sounds like the ABS self test. Nothing to worry about
if it is. sounds normal.

F.Y.A.

 

It's definitely not the ABS system - I know what that sounds like. This is something else. After playing around with it today, I think it's somehow related to the rear, right brake. I'm going to put it up on stands this weekend and give the setup a good review to see what's up. If anyone has any other suggestions, I'm all ears.

-townsley-
2003.0 Premium BS/Willow 5AT Sedan
ZTube/K&N Filter/Sport Suspension
Grounded/Tinted/Splash Guards
Lip spoiler/Aluminum Pedals
Battery Disconnect Switch

 

Its the self-adjusters on the rear brakes.

 

I'm unfamiliar with the self-adjusters - what's that?


-townsley-
2003.0 Premium BS/Willow 5AT Sedan
ZTube/K&N Filter/Sport Suspension
Grounded/Tinted/Splash Guards
Lip spoiler/Aluminum Pedals
Battery Disconnect Switch

 

Years ago, as brake shoes wore, you would have to use a special tool to reach inside the brake drum and adjust the distance between the shoe and the drum. For the emergency/parking brake you would have to shorten the cable connecting the brake handle/pedal and the rear brake. A good description of self-adjusters (with pictures) is at: http://www.educationrevolution.org/brake.html
Your probably hearing the self-adjuster for the parking brake.