Research Bulletin 1993-4

Thermal Expansion of Saturn Composite Panels

The thermolplastic vertical exterior body panels on Saturn vehicles physically increase in size as they warm and decrease during cooling. Although the vehicle's steel outer panels also expand and contract with temperature changes, the rate and amount of movement is considerably less with steel than composite materials. This dissimilar movement must be carefully considered during collision repairs.

Because of these expansion and contraction differences, it is important that the body repair technician install these panels according to the manufacturer's recommendations. Saturn has designed a Growth Management System, that utilizes a fastening arrangement and exterior panel design which control the direction of panel growth, Photographs 1 and 2.

Steel shoulder bolts with a plastic spring washer hold the panels in place, and must be torqued to the recommended value for each location. Since a variety of bolts are used throughout the vehicle, it is important that the correct steel shoulder bolt and plastic spring washer be used in the proper location. A series of round and slotted holes in each body panel controls the direction each panel is allowed to move, Photograph 3.

Proper fastening guaranties adequate compression of the joint to retain and position each panel, yet permits the panel to slide along the slot during thermal movement.

If a slotted hole, or a round (net) hole, does not line up to the space frame do not modify the shape or size of the outer panel hole. Any misalignment of the space frame must be corrected before the exterior panels can be installed. For a panel to move as designed, recommended tightening sequence and torque values as well as clearance and flushness specifications must be followed.

The information in this bulletin has been assembled from the Saturn Body/Collision Repair Service Manual 1991-1993.

Saturn has the following publications available for their vehicles:

Owner's Handbook
Product Service Publications
Service/Body Manuals
Part Catalogs
Service System User Guides

These publications can be ordered from:

Adistra Marketing and Support Services
Attn: Saturn Publications
100 Union Street
P.O. Box 1000
Plymouth, MI 48170
Phone: 313-425-2600 1-800-828-2112, prompt 3
FAX: 313-459-6861

Saturn also has two videotapes available, Encapsulated Glass Replacement and Saturn Structural Repair which can be ordered through:

Kent-Moore Tools & Equipment
1-800-468-6657

Torque Values Nm (inch-lbs)

Component Coupe SC
Front Fender (Tightening Sequence), Photograph 4. 10 Nm (89 in lbs)
Front Door (Tightening Sequence), Photograph 5. 6 Nm (53 in lbs)
Quarter Panel (Tightening Sequence), Photograph 6. 10 Nm (89 in lbs)

Component	Coupe SC
Front Fender (Tightening Sequence), Photograph 4.	10 Nm (89 in lbs)
Front Door (Tightening Sequence), Photograph 5.	6 Nm (53 in lbs)
Quarter Panel (Tightening Sequence), Photograph 6.	10 Nm (89 in lbs)

Note: Use the correct fastener in the proper location. Fastener tightening sequence and Torque values must be used to ensure a long lasting quality repair.

Torque Values Nm (inch lbs)
Saturn Sedan SL1 - SL2

Component (Tightening Sequence) Sedan SL1 - SL2
Front Fender (Tightening Sequence), Photograph 7. 10 Nm (89 in lbs)
Front Door (Tightening Sequence), Photograph 8. 6 Nm (53 in lbs)
Rear Door (Tightening Sequence), Photograph 9. 6 Nm (53 in lbs)
Quarter Panel (Tightening Sequence), Photograph 10. 10 Nm (53 in lbs)

Component (Tightening Sequence)	Sedan SL1 - SL2
Front Fender (Tightening Sequence), Photograph 7.	10 Nm (89 in lbs)
Front Door (Tightening Sequence), Photograph 8.	6 Nm (53 in lbs)
Rear Door (Tightening Sequence), Photograph 9.	6 Nm (53 in lbs)
Quarter Panel (Tightening Sequence), Photograph 10.	10 Nm (53 in lbs)

Clearance and Flushness Specification
Saturn Coupe SC, Photographs 11 and 12

Location Clearance Gap Millimeters (inches) Flushness Millimeters (inches)
1. Front Fascia To Hood 6.0 +/- 1.0 (0.24 +/- 0.04) Hood +/- 0.75
2. Front Fascia To Fender Maxima 1.0 (0.04)
3. Front Fender To Hood 7.0 +/-1.0 (0.28 +/- 0.04) Hood +/- 0.75
4. Front Fender To Door 7.0 +/-1.0 (0.28 +/- 0.04) Fender +1.5 - 0.0
5. Door To Rocker 7.0 +/- 2.0 (0.28 +/- 0.08) Door +/- 0.75
6. Top Windshield To Roof No Gap Permissible
7. Door To Quarter 7.0 +/- 1.0 (0.028 - .04) Quarter +/- 0.75
8. Quarter To Rear Fascia 2.0 - 0.0/-2.0 (0.08 + 0.0/-0.08)
9. Quarter To Decklid 4.0 - 1.5/-0.0 (0.16 - 0.06/-0.0) Decklid +/- 0.75 (+0.003)
10. Backlight To Roof No Gap Permissible

Location	Clearance Gap Millimeters (inches)	Flushness Millimeters (inches)
1. Front Fascia To Hood	6.0 +/- 1.0 (0.24 +/- 0.04)	Hood +/- 0.75
2. Front Fascia To Fender	Maxima 1.0 (0.04)
3. Front Fender To Hood	7.0 +/-1.0 (0.28 +/- 0.04)	Hood +/- 0.75
4. Front Fender To Door	7.0 +/-1.0 (0.28 +/- 0.04)	Fender +1.5 - 0.0
5. Door To Rocker	7.0 +/- 2.0 (0.28 +/- 0.08)	Door +/- 0.75
6. Top Windshield To Roof	No Gap Permissible
7. Door To Quarter	7.0 +/- 1.0 (0.028 - .04)	Quarter +/- 0.75
8. Quarter To Rear Fascia	2.0 - 0.0/-2.0 (0.08 + 0.0/-0.08)
9. Quarter To Decklid	4.0 - 1.5/-0.0 (0.16 - 0.06/-0.0)	Decklid +/- 0.75 (+0.003)
10. Backlight To Roof	No Gap Permissible

Saturn Sedan SL1 - SL2, Photographs 13 and 14

Location Clearance Gap Millimeters (inches) Flushness Millimeters (inches)
1. Front Fascia To Hood 6.0 +/- 1.0/-2.0 (0.24 +/-0.04/0.08) Hood +/- 0.75 (+/- 0.03)
2. Front Fascia To Fender Maxima 1.0 (0.04) Fascia +/- 0.75 (+/- 0.03)
3. Front Fender To Hood 4.0 +/- (0.16 +/- 0.04) Hood +/- 0.75 (+/- 0.03)
4. Front Fender To Door 6.0 Fender +0.5/-2.0 (+0.02/0.08)
5. Door To Rocker 7.0 +/- 2.0 (0.28 +/- 0.08) Door +/- 2.0 (+/- 0.08)
6. Front Door Panel To Rear Door Panel 6.75 +/- 0.75 (0.27 +/- 0.03) Front Door +0.5/2.0 (+0.02/-0.08)
7. Top Windshield To Roof No Gap Permissible
8. Rear Door To Rocker 7.0 +/- 2.0 (0.28 +/- 0.08) Door +/- 2.0 (+/- 0.08)
9. Rear Door To Quarter 6.0 +/- 1.0 (0.24 +/ - 0.04) Door +/- 0.0 / -1.5 (+0.0/0.06)
10. Quarter To Rear Fascia 0.0 + 1.5/0.0 (0.0 + 0.06/0.0)
11. Quarter To Decklid 4.0 +/ - 1.0 (0.16 +/ - 0.04) Decklid +/- 0.75 (+/-0.03)
12. Backlight To Roof No Gap Permissible

Location	Clearance Gap Millimeters (inches)	Flushness Millimeters (inches)
1. Front Fascia To Hood	6.0 +/- 1.0/-2.0 (0.24 +/-0.04/0.08)	Hood +/- 0.75 (+/- 0.03)
2. Front Fascia To Fender	Maxima 1.0 (0.04)	Fascia +/- 0.75 (+/- 0.03)
3. Front Fender To Hood	4.0 +/- (0.16 +/- 0.04)	Hood +/- 0.75 (+/- 0.03)
4. Front Fender To Door	6.0	Fender +0.5/-2.0 (+0.02/0.08)
5. Door To Rocker	7.0 +/- 2.0 (0.28 +/- 0.08)	Door +/- 2.0 (+/- 0.08)
6. Front Door Panel To Rear Door Panel	6.75 +/- 0.75 (0.27 +/- 0.03)	Front Door +0.5/2.0 (+0.02/-0.08)
7. Top Windshield To Roof	No Gap Permissible
8. Rear Door To Rocker	7.0 +/- 2.0 (0.28 +/- 0.08)	Door +/- 2.0 (+/- 0.08)
9. Rear Door To Quarter	6.0 +/- 1.0 (0.24 +/ - 0.04)	Door +/- 0.0 / -1.5 (+0.0/0.06)
10. Quarter To Rear Fascia	0.0 + 1.5/0.0 (0.0 + 0.06/0.0)
11. Quarter To Decklid	4.0 +/ - 1.0 (0.16 +/ - 0.04)	Decklid +/- 0.75 (+/-0.03)
12. Backlight To Roof	No Gap Permissible

Saturn Wagon SW1 - SW2, Photograph 15

Location Clearance Gap Millimeters (inches) Flushness Millimeters (inches)
1. Roof Panel To Liftgate 8.0 ± -2.0 (0.31 ± .08) Roof Flush 0.0 + 2.0 (00.08)
2. Liftgate Glass To Liftgate No Gap Permissible
3. Rear Door Secondary Seal To Quarter Window No Gap Permissible
4. Liftgate To Quarter Window 4.5 + 1 -0 (0.18 + 0.04 -0) Quarter Window ± (± 0.04)
5. Liftgate To Quarter Panel Gap 8.0 ± 2.25 (0.31 ± 0.086) Liftgate ± 1 (± 0.04)
6. Taillamp To Liftgate Gap 7.0 ± 2.0 (0.28 ± 0.09) Lamp Flush 0.0 + 6.5 (0, +0.27)
7. Liftgate To Fascia Gap 8.0 + 1.5, -3.5 mm (0.31 + 0.06, -0.14) Quarter +/- 0.75
8. Centerline Liftgate To Fascia Gap 6.8 + 1.5, -3.5 (0.27 + 0.06, -0.14)

Location	Clearance Gap Millimeters (inches)	Flushness Millimeters (inches)
1. Roof Panel To Liftgate	8.0 ± -2.0 (0.31 ± .08)	Roof Flush 0.0 + 2.0 (00.08)
2. Liftgate Glass To Liftgate	No Gap Permissible
3. Rear Door Secondary Seal To Quarter Window	No Gap Permissible
4. Liftgate To Quarter Window	4.5 + 1 -0 (0.18 + 0.04 -0)	Quarter Window ± (± 0.04)
5. Liftgate To Quarter Panel Gap	8.0 ± 2.25 (0.31 ± 0.086)	Liftgate ± 1 (± 0.04)
6. Taillamp To Liftgate Gap	7.0 ± 2.0 (0.28 ± 0.09)	Lamp Flush 0.0 + 6.5 (0, +0.27)
7. Liftgate To Fascia Gap	8.0 + 1.5, -3.5 mm (0.31 + 0.06, -0.14)	Quarter +/- 0.75
8. Centerline Liftgate To Fascia Gap	6.8 + 1.5, -3.5 (0.27 + 0.06, -0.14)

The information provided in this bulletin is for educational purposes only. Although every effort has been made to ensure the accuracy of the information contained in this bulletin, Tech-Cor assumes no responsibility or liability for any repairs performed using information from any publication issued by Tech-Cor.

Any person performing repairs must determine whether any suggested or recommended procedures or repairs are suitable or appropriate for the particular vehicle being repaired. The repairer remains solely responsible for such determination, as well as for the proper completion of the repairs.

Reproduction of this bulletin is not permitted without the written approval of Tech-Cor.