Suspension/Driveline - Booming Noise in Interior: Overview

Bulletin No.: 00-03-09-001

File In Section: 03 Suspension

Date: January, 2000

Subject:
Rolling Boom Noise Inside Vehicle
(Install Pinion Nose Damper and/or New Rear Leaf Spring Dampers)

Models:
1995-2000 Chevrolet and GMC M/L Van Models

Condition

Some owners may comment about a "boom" noise inside the vehicle while driving at speeds ranging between 97-105 km/h (60-65 mph). This condition is most noticeable from behind the driver's seat.

Cause

The condition may result from an engine-firing harmonic, which becomes noticeable at torque converter clutch (TCC) lock-up.

Correction

A new rear leaf spring damper kit (one per spring) has been developed, to be used in conjunction with a pinion nose damper tuned to 86 Hertz (Hz), to reduce the resultant noise level.

AFFECTED VEHICLES MAY REQUIRE THE INSTALLATION OF THE PINION NOSE DAMPER, THE SPRING DAMPERS, OR BOTH. THE INSTALLATION OF EITHER OF THESE DAMPERS IS AT THE DISCRETION OF THE TECHNICIAN FOR BEST RESULTS. Use the following procedures and the appropriate part number listed.

Important:
Installation of these dampers will not totally eliminate the boom noise. The boom noise may only be reduced to a more acceptable level. There may be other boom noises, such as body or exhaust, associated with the vehicle and this fix may either diminish or enhance the noise. These other noises should be addressed prior to the correction for the TCC boom dampener being installed.

Parts Information

P/N Description Qty

15042486 Damper Kit, Rear Spring Vib. 2
15006567 Damper Kit, Rr Axle Vib. 1
(w/86 Hz Damper)

Parts are currently available from GMSPO.

Warranty Information

For vehicles repaired under warranty, use:

Labor Operation Description Labor Time

E6200 Damper to 1.4 hrs
Spring - Install
Add To Install Pinion 0.5 hr
Nose Damper
F4000 Pinion Nose 0.6 hr
Damper - Install
Add To Install Leaf 1.3 hrs
Spring Damper

These are unique labor operation numbers for use only with this bulletin. These numbers will not be published in the Labor Time Guide.