420SEL (126.035) V8-4.2L (116.965) (1986)
Brake Rotor/Disc: All Technical Service Bulletins
Brakes - (Front) Pulsation When Braking
REF. NO. 42/5a
To: OUR MERCEDES-BENZ PASSENGER CAR DEALERS
DATE: February 1989 (supersedes MBNA 42/5 & 42/107)
SUBJECT:
PULSATION FROM FRONT BRAKES
MODEL 126 AS OF MODEL YEAR 1986
Note:
This Service Information contains new information concerning VPC installation of the new brake pads as per paragraph one.
As of January 1989, the VPC's are installing the brake pads (part number 000 420 94 20 or 000 420 95 20), mentioned in the following paragraph. The
brake pads can be identified by one yellow and one green paint mark, or just one green paint mark (depening on manufacturer), adjacent to the thickness
sensor cutout when the wheels are turned to the stop position.
We were made aware of customer complaints regarding pulsation felt through the steering wheel and possibly the vehicle body when braking on model
126 vehicles (as of January 88 production), or on older vehicles after replacement of brake pads with part number 001 420 75 20. In these cases the front
brake pads should be replaced with part number 000 420 94 20 or 000 420 95 20. Also the brake discs must be either replaced or machined.
Warning!
Assume all brake dust contains asbestos and conduct brake rears accordingly. Make certain that OSHA recommended equipment and methods are
utilized to minimize asbestos exposure to dealer personnel. (Refer to Standard Equipment Program Catalog for approved equipment.) Do Not use
compressed air blowing or dry brushing without a vacuum enclosure to clean brakes!
Before machining a brake disc make certain that the minimum thickness, indicated in the casting of a brake disc, will be exceeded by a 1.0 mm wear
tolerance, after completion of the job.
A warranty claim may be submitted for parts and labor (incl. sublet work). Claims will be rejected for any non-genuine Mercedes-Benz parts, or discs
exceeding wear tolerances specified above.
When machining the brake discs, the following parameters for final machining must be observed:
Maximum feed rate - 0.002 inch/revolution
Maximum depth of cut - 0.003 inch
Spindle speed - approx. 200 rpm
For additional information, see Service Information 42/4 dated May 1988.
Parts Information
All dealer inventory of part number 001 420 75 20 should have been returned by December 15, 1988 to the facing Parts Distribution Center, as per the
original Service Information issue.
In Case of warranty
Damage Code
Refer to Damage Code Manual