i have replaced collars and tried using washers on my 5th gen but nothing works. the washers stop the big knock but it now has a low pithced knock. collars do nothing at all. if anyone else has ideas please let me know.

 

I'm assuming you lowered you car. if so and you are using stock shocks, did you trim the bump stops? depending on how low that might fix your problem.

 

you already posted this same question, and we agreed you need new shocks.

 

Check the rear sway-bar links... Rock the rear end side to side, and listen for a knocking sound

 

i rocked it side to side and no noise, but thanks for the help anyway.