Knocking sound under braking...

[Daytona675]

Oh wise forum, I seek your knowledge...

I recently replaced my rear brake shoes and later found an unusual knocking noise from the rear under breaking. It's somewhat between a knock and a rumble. I do feel it somewhat in the floor board.

Here's what I've found so far. When I jack the rear of the car up, I can hold the left rear tire at 9 and 3 o'clock and get a small wiggle which creates a quiet knock. Upon further inspection, the source of the wiggle is the 'rear suspension cross bar assembly' (48740-aa020) as defined by Toyota, or other sites refer to this part as the 'Aft Left Rear Side Control Arm'.

Do you think that under heavy braking this could be the source of the noise? Toyota wants $123 bucks for the part. Other online discount part stores, about $94.00.

Thoughts?

[toyomoho]

The rear suspension bushings should be tight not loose. Try temporally jamming something between the outside bushing housing and inner bolt tube to take out the play. See if this quiets the noise. Might be able to just replace the worn bushing if you can find it.

[digmycelica]

Originally Posted by Daytona675

Oh wise forum, I seek your knowledge...

I recently replaced my rear brake shoes and later found an unusual knocking noise from the rear under breaking. It's somewhat between a knock and a rumble. I do feel it somewhat in the floor board.

Here's what I've found so far. When I jack the rear of the car up, I can hold the left rear tire at 9 and 3 o'clock and get a small wiggle which creates a quiet knock. Upon further inspection, the source of the wiggle is the 'rear suspension cross bar assembly' (48740-aa020) as defined by Toyota, or other sites refer to this part as the 'Aft Left Rear Side Control Arm'.

Do you think that under heavy braking this could be the source of the noise? Toyota wants $123 bucks for the part. Other online discount part stores, about $94.00.

Thoughts?

Since this seems to have happened just after you did the rear brakes, It is probably related to that.
Is this drum brakes or disc?
If it is drum then you just need to adjust the rear brake shoes a little more to get rid of the noise and make sure you removed all the old dust from the drum.
If it's disc then you need to check to make sure all the clips and shims are in place and also make sure the caliper bolts are tight.