Noise from front assembly, fault diagnosis hints

SERVICE INFORMATION
Bulletin Nbr:	731-1821
Date: ...........	February 1998
Market:	All

Noise from front assembly, fault diagnosis hints

1.	Washer (black)

2.	Support bearing

3.	Thrust bearing

4.

Washer

5.	Strut support

6.

Support

7.

Spacer

8.	Lower spring seat

Cars affected

Saab 900 model year M94-97, see limitation under respective fault symptom.

Background

These fault diagnosis procedures should be used if the customer has problems with noise from the front assembly. Measures to be taken after customer complaint. The noise can be caused by any of the following six alternatives, or a combination of them:

1.	Ticking noise, M94-97.

2.	Scraping when turning steering wheel, M94-95.

3.	Thumping noise when driving on more extremely uneven surfaces, M94-97.

4.	Thumping noise during extensive suspension movements, M94- up to and including VIN V2009638 (3D/5D) and V7002330 (CV).

5.	Scraping noise when the car is moving, M94- up to and including VIN V2040672 (3D/5D) and V7010907 (CV).

6.	Creaking or rubbing sound when driving on uneven surfaces or when turning the steering wheel, M94- up to and including VIN W2002120.

Parts required

45 44 276 Support bearing (CA: 30558303)

42 46 377 Thrust bearing (CA: 30550208)

49 07 663 Washer (CA: 30567897)

45 44 979 Strut support (CA: 30560962)

46 89 378 Spacer (CA; 30566155)

30 15 971 Underseal (CA: 30543834)

1 Ticking noise, M94-97.

The noise can be caused by the support bearing (2) moving in relation to the body.

Undo the nuts on the support bearing screws and apply a drop of underseal 30 15 971 as a lubricant between the support bearing housing and the body. Avoid getting underseal on the threads.

Tighten the three nuts alternately.

Tightening torque 18 Nm (13 lbf ft).

Warranty/Time information

Failed Object: 73133

Fault/Reason code: 40

Location code: 09

Warranty Type (US): 01

Repair/Action code: 07

Labour Operation: (CA: E9995, 0.1)

(US): 0.2 straight time

Time: 0.1

2 Scraping when turning steering wheel, M94-95.

The sound can be caused by a defective thrust bearing (3) in the upper MacPherson strut mounting.

Open the bonnet and check the black washer (1) at the top of the MacPherson strut. If it out of position and is leaning slightly towards the passenger compartment, the thrust washer (3), part no. 42 46 377, must be changed. See "7. Front suspension, Adjustment/Replacement, MacPherson strut" .

Also check the support bearing (2) and change before assembling the MacPherson strut if necessary.

Warranty/Time information

Failed Object: 73113

Fault/Reason code: 40

Location code: 09

Warranty Type (US): 01

Repair/Action code: 01

Labour Operation (US): 73130 0.7 (One side)

73134 1.2 (Both sides)

(CA: E3920 R/side, E3921 L/side)

Time: 0.9

3 Thumping noise when driving on more extremely uneven surfaces, M94-97.

This can be caused by the small washer (4) under the support bearing (3) being deformed.

Replace the washer, part no. 45 44 946, with a reinforced washer, part no. 49 07 663. See "7. Front suspension, Adjustment/Replacement, MacPherson strut".

In addition, it is very important that the upper spring seat (5), part no 45 44 979, is checked and replaced if necessary. The centre of the strut support may be bent upward if it has been in contact with the bump stop in the MacPherson strut. The strut support can then come in contact with the washer (4), causing the noise.

Warranty/Time information

Failed Object: 73137

Fault/Reason code: 40

Location code: 09

Warranty Type (US): 01

Repair/Action code: 01

Labour Operation (US): 73130 0.7 (One Side)

73134 1.2 (Both sides)

(CA: E3920 R/side, E3921 L/side)

Time: 0.9

4 Thumping noise during extensive suspension movements, M94- up to and including VIN V2009638 (3D/5D) and V7002330 (CV).

The sound can occur when driving at low speed and with severe steering wheel movement. The sound will also be heard if the car is rocked.

Fit the zinc spacer (7) between the spring and the lower spring seat. Fit the space on both the left-hand side and the right-hand side, as the height of the car will be changed slightly. See "7. Front suspension, Adjustment/Replacement, MacPherson strut".

The spacer is available as part no. 46 89 378 and has been introduced in production from VIN V2009639 (3D/5D) and V7002331 (CV).

Warranty/Time information

Failed Object: 73117

Fault/Reason code: 40

Location code: 09

Warranty Type (US): 01

Repair/Action code: 10

Labour Operation (US): 73111 0.9 (One side)

73114 1.6 (Both sides)

(CA: E3020 R/side, E2021 L/side)

Time: 0.9

5 Scraping noise when the car is moving, M94- up to and including VIN V2040672 (3D/5D) and V7010907 (CV).

The scraping noise can be caused by one of the top edges of the support bearing (2) being too sharp.

A new support bearing, part no. 45 44 276, has been introduced in production from VIN V2040673 (3D/5D) and V7010908 (CV).

When the new support bearing was introduced, the dimension of the three bolt heads was changed from 16 mm to 13 mm. This prevents the bolt heads from coming in contact with the rubber gaiter on the support bearing, which could cause the noise.

Refer to "7. Front suspension, Adjustment/Replacement, MacPherson strut" when replacing the support bearing.

Warranty/Time information

Failed Object: 73133

Fault/Reason code: 40

Location code: 09

Warranty Type (US): 01

Repair/Action code: 01

Labour Operation (US): 73130 0.7 (One side)

73134 1.2 (Both sides)

(CA: E3920 R/side, E3921 L/side)

Time: 0.9

6 Creaking or rubbing sound when driving on uneven surfaces or when turning the steering wheel, M94- up to and including VIN W2002120.

The noise can be caused by the spring having too large a diameter so that it comes in contact with the spring seat (8).

Make sure there is a clearance between the spring and the spring seat. In addition, make sure that there are no scrape marks on the second spring coil. If necessary, replace the spring on both sides of the car. Make a point of fitting/replacing the spacer (7). See "7. Front suspension, Adjustment/Replacement, MacPherson strut".

Warranty/Time information

Failed Object: 73111-02

Fault/Reason code: 40

Location code: 09

Warranty Type (US): xx

Repair/Action code: 01

Labour Operation (US): 73111 0.9 (One side)

73114 1.6 (Both sides)

(CA: E3020 R/side, E3021 L/side)

Time: 1.6