I found this TSB:
RATTLE/LOOSE LUMBER NOISE FROM FRONT OF VEHICLE
TECHNICAL SERVICE BULLETIN
Reference Number(s): 53-33-04; 53-33-04A
RATTLE/LOOSE LUMBER NOISE FROM FRONT OF VEHICLE WHEN
DRIVING OVER BUMPS (DIAGNOSE/REPAIR PROCEDURE)
Model(s): 1994-96 Cadillac Concours, DeVille, Eldorado, Seville
Section: 3 - Steering/Suspension
Bulletin No.: 53-33-04A
Date: April, 1996
VEHICLES AFFECTED
1994-96 Cadillac Concours, DeVille, Eldorado, Seville with 4.9L, 4.6L engine (VINs B, Y, 9 - RPOs L26,
LD8, L37).
CONDITION
Some owners may comment on a clunk, rattle, or loose lumber noise from the front of the vehicle when driving
over small bumps at low speeds.
CAUSE
This condition may be due to a number of different sources. These include, but are not limited to:
.. Loose strut mounting bolts.
.. Loose stabilizer bar link pivots.
.. Coil spring clash (1995 DeVille only).
.. Noisy front upper strut mounts.
.. Noisy engine mount.
The use of Kent-Moore tool J 39570, ChassisEAR, is recommended when attempting to identify the source of
the rattle. It is IMPORTANT to note:
NOTE: This bulletin supersedes Corporate Bulletin number 53-33-04, (Section 3 -
Steering/Suspension).
1996 Cadillac Seville STS
RATTLE/LOOSE LUMBER NOISE FROM FRONT OF VEHICLE
Wednesday, November 23, 2005 7:59:47 PM Page 1 © 2004 Mitchell Repair Information Company, LLC.
.. Properly functioning cars WILL transfer noise to the ChassisEAR.
.. If not familiar with noise from a known good car, comparison MUST be made between a "good" car and
the car to be evaluated.
CORRECTION
The following corrections only address the sources listed above. Other sources are possible and may require
attention not outlined here.
1. Check the strut mounting bolt fasteners for proper torque:
.. Upper (to body): 24 N.m (18 ft-lb).
.. Lower (to knuckle): 229 N.m (168 ft-lb).
.. Damper shaft nut: 75 N.m (55 ft-lb).
2. Check torque of stabilizer bar link attachment points:
.. 1994: 65 N.m (48 ft-lb).
.. 1995-96: 55 N.m (40 ft-lb).
3. If the torque is correct in Step 1, disconnect stabilizer bar links and determine if noise is gone. If it is,
replace the stabilizer bar links.
.. 1994 link: P/N 3523593.
.. 1995-96 link: P/N 3530406.
4. Some 1995 DeVilles may exhibit a condition known as "spring clash". This is a metallic clunk noise from
the front of the vehicle. This spring noise is due to low spring load allowing the first inner spring coil to
"clash" against the second coil during compression. To correct this condition, install coil spring, P/N
22132857 (one or both). This is a redesigned spring and meets trim height specification. THIS SPRING
IS FOR VEHICLES BUILT UP TO AND INCLUDING VIN SU266448. VEHICLES BUILT AFTER
THIS VIN ALREADY HAVE THE REDESIGNED SPRING INSTALLED.
5. A loose lumber noise may be heard by driving at speeds typically between 10 - 45 MPH over both
smaller sharp bumps and larger bumps (more prevalent on small sharp bumps). Replace the front upper
strut mounts with P/N 22174949.
.. Noise will be heard if ChassisEAR is attached to the strut. You will need to familiarize yourself to
NOTE: Do not over-torque damper shaft nut as it could damage the upper strut
mount.
NOTE: Do not allow the ball stud to rotate during tightening of the nuts or the link
may be damaged.
NOTE: To distinguish between Steps 4 and 5, use the ChassisEAR J 39570 and
attach clips to the front engine mount and upper strut mount shock tower
area. Please note:
1996 Cadillac Seville STS
RATTLE/LOOSE LUMBER NOISE FROM FRONT OF VEHICLE
Wednesday, November 23, 2005 7:59:48 PM Page 2 © 2004 Mitchell Repair Information Company, LLC.
a non-complaint car. Normal operating sounds may lead you to service a good car.
.. More noise will be heard if ChassisEAR is attached to the strut rod top nut than to one of the three
strut mount fasteners in the strut tower. You will hear strut operating noises in the nut, while the
noise heard in the strut mount fasteners will be more quiet since the job of the strut mount is to
dampen. Any noise heard from the strut rod is likely normal; strut replacement will NOT affect this
noise. To verify, compare to a known good car.
.. Assure that ChassisEAR clips are securely affixed. Any movement of the clips to the fastening
point may result in false noise being generated.
.. Do not test drive the vehicle with the hood open to the secondary latch as the hood movement can
make false noise. Latch the hood fully.
6. If the lumber noise is produced at speeds only below 20 MPH while driving over a larger bump, then it
may be engine mount related. This noise sounds as if it is coming from the middle to under dash area,
while Step 4 sounds as if it is coming from above the dash. On vehicles equipped with a 4.6L engine,
replace the left engine mount and the right transaxle mount. On vehicles equipped with a 4.9L engine,
replace the left engine mount only.
.. 4.6L left engine mount: P/N 22171688.
.. 4.6L right transaxle mount: P/N 22171682.
.. 4.9L left engine mount: P/N 22171683.
PARTS INFORMATION
Parts are currently available from GMSPO.
WARRANTY INFORMATION
For vehicles repaired under warranty, use:
WARRANTY INFORMATION
Labor
Operation
Description Labor Time
E3857 Step 1 0.4 Hr.
E2147 Step 2 Use published labor operation
time.
E3020 Step 3 (Right Spring Only) Use published labor operation
time.
E3021 Step 3 (Left Spring Only) Use published labor operation
time.
E3027 Step 3 (Both Springs) Use published labor operation
time.
E3927 Step 4 (Mount Assembly, Both) Use published labor operation
time.
J1501 Step 5 (Left Engine Mount, Only) Use published labor operation
time.
1996 Cadillac Seville STS
RATTLE/LOOSE LUMBER NOISE FROM FRONT OF VEHICLE
Wednesday, November 23, 2005 7:59:48 PM Page 3 © 2004 Mitchell Repair Information Company, LLC.
K6720 Step 5 (Left Transaxle Mount,
4.6L)
Use published labor operation
time.
J1501 Step 5 (Left Engine Mount, 4.9L) 1.2 Hrs.
1996 Cadillac Seville STS
RATTLE/LOOSE LUMBER NOISE FROM FRONT OF VEHICLE