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Brakes - Front Brake Squeal/Grind Applied or Not

Date: December 5, 2005

Order No.: P-B-42.10/51d

Supersedes: P-B-42.10/51c dated March 15, 2005

Group: 42

Revision:
Applicable Models, Work Procedure, Parts and Warranty Information Updated

SUBJECT:
Model 171.456

Model 203.065/076

Model 209.376/476, up to Vehicle Production 06/2004

Model 209.375/475

Model 211.056, up to Vehicle Production 08/2005

Model 211.070

Model 215.375/376/378

Model 219.375

Model 220.067/170/175/176/178

Model 230.475

Front Brake Squealing / Grinding Noise

If you receive customer reports in the above model vehicles of a squealing or grinding noise from the front brakes, even when the brakes are not applied, perform the following.





1. Inspect the front brake discs and pressure retaining springs for contact. If contact exists, replace the brake pad pressure retaining spring(s) with modified parts (Figure 1) after checking the brake lining per Step 2.

Note:
The squealing/grinding noise when the brakes are not applied is the result of the pressure retaining spring slipping out of position and scraping on the face of the brake disc. Each time the brakes are applied, the play within the brake caliper guide channel causes the brake pads to move a short distance in the circumferential direction of the brake disc. This movement is then transmitted to the two retaining pins, which consequently rotate a small amount during each brake application. This rotation is then transmitted to the pressure retaining spring, which can cause it to dislodge from its original position. The revised pressure retaining springs incorporate retainer tabs (Figure 1, red circles).





2. Check the version of the brake lining by comparing the designation imprinted on the backing plate (Figure 2), with that listed within the parts information table. Replace brake pads if necessary and install the correct version for the respective vehicle as notated within the parts information table. Reference the following WIS documents.

Model 171-AR42.10-P-1600VA

Model 203/209 - AR42.10-P-1600PF (valid for 209 up to 4/23/04) or AR42.10-P-1600AC (valid for 209 as of 4/24/04)

Model 211/230-AR42.10-P-1600R

Model 219-AR42.10-P-1600TX

Model 215/220 AR42.10-P-01601 and AR42.10-P-01611

3. Install piston dampers in the pistons of the front brake calipers. The piston damper must be inserted into the piston with the rounded part first.





Parts Information

Note:
The following allowable labor operations should be used when submitting a warranty claim for this repair.





In Case of Warranty

Note:
If this repair is done in conjunction with other brake services, only the parts can be claimed to warranty.

Note:
This document does not extend warranty beyond the posted limits for brake pads.