2020 Mercedes Benz Truck ML 350 Technical Service Bulletin # LI46-20_P-055943 Date: 130424

2020 Mercedes Benz Truck ML 350 Technical Service Bulletin # LI46-20_P-055943 Date: 130424

Steering - Noises and Guidelines for Detection

Noises from the steering system (guidelines for detecting noise)

Topic number L146.20-P-055943

Version 1

2020 Mercedes Benz Truck ML 350 4MATIC (164.186) V6-3.5L (272.967) Page 349

Design group 46.20 Steering gear

Date 04-24-2013

Validity Model 164/251

Reason for change

Complaint:

1.) Rattling noises from the area of the steering column tube on rough roads or when driving over road bumps

2.) Cracking noises when braking or accelerating, which may also be perceptible at the steering wheel at the same time

3.) Rattling noises from the area of the steering gear on rough roads or when driving over road bumps

Cause:

1.) Play or incorrectly engaged firewall pivot point

2.) Play or incorrectly engaged firewall pivot point, or slip/stick effect of steering coupling

3.) Play between thrust piece and toothed rack of steering

Attachments

Remedy:

For noise diagnosis the use of the STEELMAN ChassisEAR is helpful and it must always be used if there is any uncertainty in order to clearly

identify the cause of the noise.

Re. causes 1 and 2:

Check version of firewall pivot point and check for play:

2020 Mercedes Benz Truck ML 350 4MATIC (164.186) V6-3.5L (272.967) Page 350

a) Check the version -> If an old version (see Figure 001 version "2" or Figure 002 version "4") is installed, the current version (see Figure 001

version "3" or Figure 002 version 3) must be installed.

The new version of the firewall pivot point is installed in production as of VIN 164.### - # A - 220353 or 251.### - # A - 053080.

2020 Mercedes Benz Truck ML 350 4MATIC (164.186) V6-3.5L (272.967) Page 351

b) Check that the bearing is installed without play and properly engaged -> A white stripe must be visible (see Figures 003 and 004).

Note:

Also refer to the TIPS document "Cracking noises from the area of the steering shaft".

Re. cause 2:

Check steering coupling slip/stick effect:

- Remove steering coupling - Push steering coupling together in sliding piece and pull apart; if a pressure point can be felt, the coupling must be

2020 Mercedes Benz Truck ML 350 4MATIC (164.186) V6-3.5L (272.967) Page 352

replaced

Re. cause 3:

Check play between thrust piece and toothed rack of steering. and adjust if necessary:

- Check steering effect with simplified test method, see TIPS document "Rattling/thumping noises from the area of the steering (simplified test

method)" L146.20-P-053398

- Adjust play between thrust piece and steering rack if necessary