Service Bulletin

Bulletin No.:

19-NA-129

Date:

May, 2021

TECHNICAL
Subject:
Brand:

Squeak and/or Clunking Noise from Rear of Vehicle
Model:

Model Year:
from

to

2019

2019

Date Breakpoint:
from

Engine:

Transmission:

All

All

to

Silverado 1500
(New Model)
Chevrolet

Silverado 1500
(New Model - 12th
VIN Digit = 7)
- 4WD

GMC

Sierra 1500 (New
Model)

Chevrolet

Silverado 1500

GMC

Sierra 1500

2020

2021

Involved Region or Country

North America, Middle East, Paraguay, Uruguay, Chile and Thailand

Condition 1

Some customers may comment on a squeak type noise heard from the rear of the
vehicle.
Upon further investigation, the technician may diagnose the noise is coming from the rear
suspension leaf spring area.

Condition 2

Some customers may comment on a clunking type noise heard from the rear of the
vehicle.
Upon further investigation, the technician may diagnose the noise is coming from the rear
suspension leaf spring area.

Cause

This condition may be caused by debris getting between the leaf springs and/or loose
U-Bolts.

Correction 1

Note: 2020 vehicles built at Silao after March 17, 2020, or built at Fort Wayne after
June 11, 2020 (and all 2021 models) are possible candidates for torque relaxation at the
U-bolt to axle and the 1610 km (1000 miles) break-in period, but should NOT have new
inserts installed. The service inserts are the same as the production inserts.
For earlier built vehicles, install new rear leaf spring inserts, following the Service
Procedure below.

Correction 2

Note: Vehicles built after the 2020 breakpoints noted above, (and all 2021 models) may
still have torque relaxation at the U-bolt to axle and should have the re-torque performed.
Re-torque the U-bolts of the leaf spring assembly, following the Service Procedure below.

Copyright 2021 General Motors LLC. All Rights Reserved.

Page 2

May, 2021

Service Procedure (Condition 1)
Prior to performing this bulletin, follow the procedure for
Noise Diagnosis - Rear Suspension in SI to determine
the source of the noise. Jounce the rear of the vehicle
utilizing J 39570 Chassis Ear or equivalent, to aid in
locating the source of the noise.
If necessary, road test the vehicle.
1. Raise the vehicle on a frame lift-type hoist. Refer to
Lifting and Jacking the Vehicle, in SI.
2. Inspect the rear leaf springs and shackles for
damage.
• If damage has been found, refer to Rear Spring
Shackle Replacement or Leaf Spring
Replacement (1500), in SI.
• If damage has NOT been found, proceed to the
next step.

Bulletin No.: 19-NA-129

3. Install new Rear Leaf Spring Inserts using the
following procedure:
3.1. Clean the springs using high-pressure water
or a steam cleaner to remove any lubricant or
contamination from between the leaf
elements, paying special attention to the tip
contact areas.

5341854

Caution: Do NOT damage the finish on Leaf Springs.
3.2. On the spring assembly, insert a plastic trim
tool or plastic wedge in between the #1 and
#2 leaf springs, to access the old insert.

5341853

Bulletin No.: 19-NA-129

May, 2021

Page 3

5341855

3.3. Push up on insert until it hits the bottom of the
spring above it. Then use a suitable cutting
tool to cut the stem off from the insert.

5341857

5341856

3.4. Remove the top portion of the insert, and then
remove the bottom portion of the
remaining stem.

3.5. Using a rag and degreaser, clean any dirt or
grease from between the leaf springs at the
insert location.

Page 4

May, 2021

Bulletin No.: 19-NA-129

The gray spring inserts are designed to work with
absolutely no lubricant. Lubricants of any kind
must never be used on the gray spring tip inserts
and any remaining lubricant must be completely
removed when installing new tip inserts.
5. Lower the vehicle to the ground and test drive to
verify the repair.
Note: If the vehicle returns with noise after this
procedure, and there is no loss of torque at the U-Bolts,
thoroughly clean the spring contact points with high
pressure water or a steam cleaner to remove
contaminants from between the spring elements.
Contaminants, grease, undercoating or any substance
in the leaf interface will cause noise when the spring
elements move over each other.
Important: If the Service Procedure for Condition 1
fixes the squeak, DO NOT proceed to Service
Procedure (Condition 2).

Service Procedure (Condition 2)
5341859

Caution: Do NOT damage the surface of the new
insert when trimming
3.6. Cut the stem of the new insert with a hacksaw
or suitable cutting tool. Make sure to leave 6
mm (0.240 in) of the stem.

1. Support the vehicle at curb height to relieve the
tension on the leaf springs, when re-torqueing the
leaf spring U-bolt nuts.

5357922

5341861

3.7. Apply a small amount of RTV sealer around
the remaining portion of the stem.
3.8. Install the new insert into the leaf spring.
Make sure the stem portion lines up with the
slot in the spring. Remove the plastic trim tool
or plastic wedge to close the spring and seat
the new insert.
4. Repeat step #3 for the 3 remaining inserts.
Important: After a new vehicle is delivered to a
customer, or new spring tip inserts are installed per this
bulletin, new inserts have a break-in period of up to
1610 km (1000 miles), where some noise can be
expected.

2. Loosen the anchor plate U-bolts (1).
Warning: Ensure that the proper torque procedure
for the U-Bolts is followed in SI. Excessive fastener
torque will extrude, and damage, the spring
isolators making the condition worse.
3. Re-torque the anchor plate U-bolts (1). Refer to
Fastener Specifications in SI.
4. Repeat steps # 2 and 3 for the opposite side leaf
spring.
5. Re-test the vehicle for the same clunking noise. If
the issue remains, follow the regular repair
procedure.

Bulletin No.: 19-NA-129

May, 2021

Page 5

Parts Information
Causal
Part

Description

Part
Number

Qty

INSERT-RR
SPR LEAF

84855893

4

RTV Sealer

88864346
(In Canada,
88861418)

1

N/A

Warranty Information
For vehicles repaired under the Bumper-to-Bumper
coverage (Canada Base Warranty coverage), use the
following labor operation. Reference the Applicable
Warranties section of Investigate Vehicle History (IVH)
for coverage information.
Labor Operation

Description

Labor Time

8080598*

Replacement of 4 Rear Leaf Spring Inserts (Condition 1)

0.5 hr.

8080608*

Retorque U-Bolts / Road Test (Condition 2)

0.6 hr.

*This is a unique Labor Operation for Bulletin use only.

Version

4

Modified

Released August 06, 2019
Revised March 02, 2020 – Added 2019 Silverado 1500 (New Model - 12th VIN Digit = 7) 4WD model and 2020 Model Year, Added Breakpoint and Updated Insert Part Number.
Revised February 08, 2021 – Updated Breakpoints, Separated Repair Procedures to
Address Condition #1 and Condition #2, Updated Warranty Information.
Revised May 05, 2021 – Added 2021 Model Year, Information to Clarify the Breakpoint
Strategy and to Emphasize that the Inserts (GM P/N 84855893) Have a Break-in Period
of Approximately 1610 km (1000 miles).

GM bulletins are intended for use by professional technicians, NOT a "do-it-yourselfer". They are written to inform these
technicians of conditions that may occur on some vehicles, or to provide information that could assist in the proper
service of a vehicle. Properly trained technicians have the equipment, tools, safety instructions, and know-how to do a
job properly and safely. If a condition is described, DO NOT assume that the bulletin applies to your vehicle, or that your
vehicle will have that condition. See your GM dealer for information on whether your vehicle may benefit from the
information.

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