SPECIAL POLICY BALL JOINTS (GREASABLE) UPPER & LOWER
SUBJECT: SPECIAL POLICY ADJUSTMENT - GREASEABLE UPPER & LOWER CONTROL ARM BALL JOINTS AND FRONT END ALIGNMENT PARTS KIT
MODELS: 1988-90 C/K TRUCKS
THIS BULLETIN CANCELS AND REPLACES GMC TRUCK SERVICE BULLETIN 90-3C-60(A) DATED DECEMBER, 1990 TO REVISE THE SERVICE PROCEDURE AND THE LABOR TIMES. ALL COPIES OF 90-3C-60(A) SHOULD BE DISCARDED. REVISIONS TO THIS BULLETIN INCLUDE ADDITION OF A REQUIREMENT TO CHECK THE CONDITION OF 1990 MODEL YEAR C/K MAINTENANCE-FREE BALL JOINTS BEFORE REPLACEMENT, ELIMINATION OF CASTER/CAMBER ALIGNMENT AND ADDITION OF TOE-IN ALIGNMENT.
Ball Joints:
A contaminated front suspension ball joint can cause squeaking while turning and/or require more frequent steering input while driving down the road. Contamination could also cause a ball joint to wear out and eventually to separate.
1988-1989
Some of the maintenance-free front suspension ball joints used on 1988 and 1989 model C/K trucks have experienced contamination.
1990
Later design maintenance-free ball joints were used in early 1990 model C truck front suspension upper control arms and K truck front suspension upper and lower control arms. Those maintenance-free front suspension ball joints used in the 1990 model C/K trucks incorporated two significant design changes that greatly reduce the possibility of contamination.
An enhancement was made at the neck of the ball stud by changing the material of the seal insert to glass-filled nylon for greater stiffness and less shrinkage when cold.
In addition, the composition of the seal was changed to make it more flexible in cold weather.
Since the first publication of the Special Policy Adjustment Bulletin, stringent lab testing, proving ground durability tests and a fleet field test have demonstrated the durability of the 1990 model C/K maintenance-free front suspension ball joints. Therefore to determine whether a customer complaint is attributable to contamination of a maintenance-free ball joint on a 1990 model truck, do not replace any such ball joint unless the ball joint wear check included in this bulletin indicates over 1 mm (0.040 inch) of lash.
Greaseable ball joints were also used in 1990 model year production as follows since:
start of production on the C truck front suspension lower control arms;
interim production on the C truck front suspension upper control arms; and
interim production on the K truck front suspension upper and lower control arms.
The greaseable style ball joint incorporates a zerk fitting to facilitate maintenance and is designed to allow grease to purge at the interface of the rubber dust cover and the ball joint shell (or socket).
Replacement Ball Joints
Greaseable ball joints should be used as replacements for contaminated maintenance-free ball joints. Since it is important to lubricate the grease- able ball joint, customers must be given the information slip, shown in figure 1, which explains the greaseable ball joint maintenance requirements. This slip is packaged in each service ball joint kit.
Front Wheel Caster/Camber
Alignment Parts Kit:
The 1988-90 C/K trucks incorporate a front suspension feature designed to improve the vehicle's ability to maintain front wheel caster/camber alignment. The front wheel alignment set by the assembly plant will not change and should not need adjustment except in cases where accident or road hazard damage has occurred. Through the listed VIN breakpoints, in customer pay situations if caster/camber alignment was performed, the customer was also charged for the required alignment parts kit. Due to the cost of the parts kit, the charge for a wheel alignment would not be competitive in today's marketplace. In view of this, GMC Truck has issued a special policy to cover the cost of the caster/camber alignment parts kit but not the installation cost. This kit is included in vehicles currently being produced.
VEHICLES INVOLVED - BALL JOINTS
YEAR MODEL PLANT FROM THROUGH COMPONENTS INVOLVED ---- ----- ------------- ----- ---------- ------------------- 1988 C/K Ft. Wayne (Z) SOP EOP All Ball Joints 1988 C/K Oshawa (1) SOP EOP All Ball Joints 1988 C/K Pontiac (E) SOP EOP All Ball Joints 1989 C/K Ft. Wayne (Z) SOP EOP All Ball Joints 1989 C/K Oshawa (1) SOP EOP All Ball Joints 1989 C/K Pontiac (E) SOP EOP All Ball Joints 1990 C Ft. Wayne (Z) SOP LZ531411 Upper Ball Joints 1990 K Ft. Wayne (Z) SOP LZ532770 All Ball Joints 1990 C Oshawa (1) SOP L1539478 Upper Ball Joints 1990 K Oshawa (1) SOP L1539477 All Ball Joints 1990 C Pontiac (E) SOP LE530629 Upper Ball Joints 1990 K Pontiac (E) SOP LE530628 All Ball Joints
VEHICLES INVOLVED ALIGNMENT PARTS KIT
YEAR MODEL PLANT FROM THROUGH ---- ----- --------------- ------- -------- 1988 C/K Ft. Wayne (Z) SOP EOP 1988 C/K Oshawa (1) SOP EOP 1988 C/K Pontiac (E) SOP EOP 1989 C/K Ft. Wayne (Z) SOP EOP 1989 C/K Oshawa (1) SOP EOP 1989 C/K Pontiac (E) SOP EOP 1990 C/K Ft. Wayne (Z) SOP LZ525988 1990 C/K Oshawa (1) SOP L1536879 1990 C/K Pontiac (E) SOP LE530905
SPECIAL POLICY ADJUSTMENT
Ball Joints:
On 1988, 1989 and 1990 models up to the VIN breakpoints, for a period of 5 years or 100,000 miles (160,000 km) of purchase, whichever occurs first, if a customer experiences contamination of any of the maintenance-free ball joints, all maintenance-free ball joints will be replaced with greaseable ball joints at no charge. However, there is a reduced likelihood that a 1990 model truck complaint of squeaking while turning, more frequent steering input while driving down the road or a symptom that a maintenance-free ball joint might be wearing out is attributable to a contaminated maintenance-free ball joint due to the improved performance of 1990 model year maintenance-free ball joints. For 1990 model trucks only, conduct the ball joint wear check included in this Bulletin to determine whether a customer complaint is attributable to contamination of a maintenance-free ball joint. Do not replace the maintenance-free ball joints in a 1990 model truck unless a ball joint check indicates over 1 mm (0.040 inch) of lash. Additionally, the customer may be eligible for reimbursement for previous repairs with supporting documentation.
Field testing has now confirmed that a 1988-90 C/K truck does not require front wheel alignment due to ball joint replacement. Therefore, caster/ camber alignment will no longer be provided upon customer request under this special policy. However, in the interest of customer satisfaction and upon customer request, a toe-in alignment may be completed after maintenance-free ball joint replacement under this special policy.
Front Wheel Caster/Camber Alignment Parts Kit: ----------------------------------------------- On 1988, 1989 and 1990 models up to the VIN breakpoints, for a period of 5 years or 100,000 miles (160,000 km) of purchase, whichever occurs first, if a customer's vehicle requires caster/camber alignment, the caster/camber alignment parts kit will be provided at no charge (but not the installation cost). Testing has confirmed that caster/camber alignment is only required due to accident or road hazard damage.
Bulletin Filing
This "SPECIAL POLICY BULLETIN" should be filed in your "SPECIAL POLICY ADJUSTMENT BULLETINS" binder.
OWNER NOTIFICATION
Owners of all vehicles involved in this SPECIAL POLICY ADJUSTMENT have been notified by GMC Truck Division (see copy of owner letter included with this bulletin).
BALL JOINT WEAR CHECK (1990 Only) The following checking procedures apply to 1990 K Model upper and lower ball joints and 1990 C Model upper ball joints only. (1990 C Models have greaseable lower ball joints).
1990 K MODEL LOWER
o Be sure the vehicle rests on a level surface.
o Raise and support front of vehicle with suitable safety stands. Support the lower control arm with a floor stand or jack as far outboard as possible.
o The vehicle must be stable and should not rock on the floor stands.
o If the vehicle is equipped with aluminum wheels it may be necessary to first remove the wheel.
Check the ball joints for vertical looseness
o With the vehicle on the jack stands, place dial indicator against the spindle to show vertical movement (figure 15).
o Pry between the lower control arm and the outer race while reading the dial indicator. This will show vertical looseness in the ball joints (figure 15).
o If the dial indicator reading is more than 1 mm (0.040-inch), replace the ball joint.
NOTICE: Do not pry between the lower arm and the drive axle seal or in such a manner that the ball joint seal is contacted. Damage to the seal will result (4 WD).
1990 C and K MODEL UPPER
o Be sure the vehicle rests on a level surface.
o Raise and support front of vehicle with suitable safety stands. Support the lower control arm with a floor stand or jack as far outboard as possible.
o The vehicle must be stable and should not rock on the floor stands.
o If the vehicle is equipped with aluminum wheels it may be necessary to first remove the wheel.
Check the ball joints for vertical looseness
o With front of vehicle supported, position dial indicator with magnetic base on frame and measurement needle on top of the upper ball joint or control arm (figure 16).
o With a pry bar, pry between the upper control arm and steering knuckle while observing the dial indicator (figure 17).
o If the reading is more than 1 mm (0.040-inch) replace the ball joint.
NOTICE: Do not pry in such a manner that the ball joint seal is contacted. Damage to the seal will result.
SERVICE PROCEDURE MAINTENANCE-FREE BALL JOINT REPLACEMENT, UPPER & LOWER:
1988-89 C TRUCK
Required Tools:
J 23742 Ball Joint Separator J 9519-D Ball Joint Remover and Installer Set J 24319-01 Steering Linkage Puller
- Raise vehicle and support it with safety jack stands. - Support lower control arm with a jack and secure spring with a safety chain.
CAUTION:
Jack or stand must remain under the lower control arm spring seat during removal and installation to retain the spring and control arm in position.
Remove (figure 2)
1. Wheel and tire assembly. 2. Brake line support (86) from upper control arm (42). 3. Brake caliper and rotor.
[!] Important Support the caliper with a piece of wire to prevent damage to the brake line.
4. Cotter pin (68) and stud nut (67) from the upper ball joint (66).
5. Upper ball joint (66) from knuckle. - Support the knuckle assembly. - Use J 23742 as shown in figure 3. - Inspect the tapered hole in the knuckle and remove any dirt. If the hole is out of round, deformed or damaged, the knuckle must be replaced.
6. Rivets from upper ball joint (66). - If ball joint has been previously replaced, remove bolts and skip to step 7. - Center punch the top of the rivets. - Use a 4.763 mm (3/16-inch) drill to cut a 6.35 mm (1/4-inch) deep hole in the center of each rivet (figure 4). - Drill the rivet heads away using a 12.7 mm (1/2-inch) drill (figure 5). - Punch the rivets out using a punch (figure 6).
7. Upper ball joint (66).
Install (figure 7)
1. New upper ball joint (66) to the upper control arm (42). - Position four attaching bolts pointing upward, washers and nuts - Tighten nuts (A) to 23 Nm (1 7 lbs. ft.).
Remove (figure 2)
1. Cotter pin (68) and stud nut (67) from the lower ball joint (69).
2. Lower ball joint (69) from knuckle. - Support the knuckle assembly. - Use J 24319-01 to break the ball joint loose from the knuckle. - Inspect the tapered hole in the knuckle and remove any dirt. If the hole is out of round, deformed or damaged, the knuckle must be replaced. - Move knuckle assembly aside and support.
3. Lower ball joint (69) from the lower control arm (40). - Use tools as shown in figure 8.
Install (figure 2)
1. New lower ball joint (69) to the lower control arm (40). - Press in the ball joint using tools in figure 9. The ball joint will bottom on the control arm.
2. New lower ball joint (69) to the knuckle.
3. Lower stud nut (67) and new cotter pin (68). - Tighten stud nut (67) to 128 Nm (94 lbs. ft.). - Align the slot in the stud nut with the hole in the stud by tightening the stud nut. - Bend the pin ends against the nut.
4. New upper ball joint (66) to the knuckle.
5. Upper stud nut (67) and new cotter pin (68). - Tighten stud nut (67) to 100 Nm (75 lbs. ft.). - Align the slot in the stud nut with the hole in the stud by tightening the stud nut. - Bend the pin ends against the stud nut.
6. Brake rotor and caliper.
7. Brake line support (86) to upper control arm (42).
8. Wheel and tire assembly.
9. Repeat above procedure on opposite side of vehicle.
MAINTENANCE-FREE BALL JOINT REPLACEMENT, UPPER ONLY, 1990 C TRUCK
Required Tools:
J 23742 Ball Joint Separator
- Raise vehicle and support it with safety jack stands. - Support lower control arm with a jack and secure spring with a safety chain.
CAUTION:
Jack or stand must remain under the lower control arm spring seat during removal and installation to retain the spring and control arm in position.
Remove (Figure 2)
1. Wheel and tire assembly.
2. Brake line support (86) from upper control arm (42).
3. Brake caliper and rotor.
Important
Support the caliper with a piece of wire to prevent damage to the brake line.
4. Cotter pin (68) and stud nut (67) from the upper ball joint (66).
5. Upper ball joint (66) from knuckle. - Support the knuckle assembly. - Use J 23742 as shown in figure 3. - Inspect the tapered hole in the knuckle and remove any dirt. If the hole is out of round, deformed or damaged, the knuckle must be replaced.
6. Rivets from upper ball joint (66). - If ball joint has been previously replaced, remove bolts and skip to step 7. - Center punch the top of the rivets. - Use a 4.763 mm (3/16-inch) drill to cut a 6.35 mm (1/4-inch) deep hole in the center of each rivet (figure 4). - Drill the rivet heads away using a 12.7 mm (1/2-inch) drill (figure 5). - Punch the rivets out using a punch (figure 6).
7. Upper ball joint (66).
Install (figure 2)
1. New upper ball joint (66) to the upper control arm (42). - Position four attaching bolts pointing upward, washers and nuts (figure 7). - Tighten nuts (A) to 23 Nm (1 7 lbs. ft.).
2. New upper ball joint (66) to the knuckle.
3. Upper stud nut (67) and new cotter pin (68). - Tighten stud nut (67) to 100 Nm (75 lbs. ft.). - Align the slot in the stud nut with the hole in the stud by tightening the stud nut. - Bend the pin ends against the stud nut.
4. Brake rotor and caliper.
5. Brake line support (86) to upper control arm (42).
6. Wheel and tire assembly.
7. Repeat above procedure on opposite side of vehicle.
MAINTENANCE-FREE BALL JOINT REPLACEMENT, UPPER & LOWER:
1988-90 K TRUCK
Required Tools:
J 36607 Ball Joint Separator J 24319-01 Steering Linkage Puller
- Raise vehicle and support it with safety jack stands. - Support lower control arm with a jack.
CAUTION:
Jack or stand must remain under the lower control arm spring seat during removal and installation to retain the torsion bar and control arm in position.
Remove (figure 10)
1. Wheel and tire assembly.
2. Brake caliper and rotor.
Important
Support the caliper with a piece of wire to prevent damage to the brake line.
3. Cotter pin (130) and stud nut (129) from the upper ball joint (115).
4. Upper ball joint (115) from knuckle (117). - Support the knuckle assembly. - Use J 36607 as shown in figure 11. - Inspect the tapered hole in the knuckle and remove any dirt. If the hole is out of round, deformed or damaged, the knuckle must be replaced.
5. Rivets from upper ball joint (115). - If ball joint has been previously replaced, remove bolts and upper ball joint and skip to step 7. - Center punch the top of the rivets. - Use a 4.763 mm (3/16-inch) drill to cut a 6.35 mm (1/4-inch) deep hole in the center of each rivet (figure 4). - Drill the rivet heads away using a 12.7 mm (1/2-inch) drill (figure 5).
6. Upper ball joint (1 15) from the upper control arm (101). Rivets will remain in control arm.
[!] Important Do not damage the upper control arm mounting surface when removing the ball joint or rivets. - Remove remaining rivet shanks flush with control arm. - Support the upper control arm and punch the rivets out using a punch (figure 6).
Install (figure 12)
1. New upper ball joint (115) to the upper control arm (101) (C truck arm shown, K truck arm typical). - Position four attaching bolts pointing upward, washers and nuts. - Tighten nuts (A) to 23 Nm (1 7 lbs. ft.).
Remove (figure 10)
1. Drive axle shaft nut (120) and washer (119) from the hub assembly (114).
2. Cotter pin (130) and stud nut (131) from the lower ball joint (127).
3. Lower ball joint (127) from the knuckle (117) - Support the knuckle assembly. - Use J 24319-01. - Drive axle must be removed from hub assembly at the same time. - Move knuckle aside and support. - Move drive axle aside and support. - Inspect the tapered hole in the knuckle and remove any dirt. If the hole is out of round, deformed or damaged, the knuckle must be replaced.
4. Rivets from lower ball joint (127). - If ball joint has been previously replaced, remove bolts and skip to step 5. - Center punch the top of the rivets. - Use a 4.763 mm (3/16-inch) drill to drill through the center of each rivet (figure 4). - Use a 7.938 mm (5/16-inch) drill to enlarge the hole through the center of each rivet. - Drill rivet heads away using a 12.7 mm (1/2-inch) drill (figure 5).
[!] Important Use caution to avoid drilling through rivet head and into lower control arm. - Use a chisel and hammer to remove any remaining rivet head. - Punch out the rivets using a punch (figure 6).
5. Lower ball joint (127) from the lower control arm (93).
Install (figure 10)
1/ New lower ball joint (127) to the lower control arm (93) (figure 13). - Ball joint is installed between flanges of lower control arm. - Position four attaching bolts pointing downward, washers and nuts. - Tighten nuts (A) to 60 Nm (45 lbs. ft.).
2. New lower ball joint (1 27) to the knuckle (117). - Drive axle should be installed through the hub assembly at the same time.
3. Lower stud nut (131) and new cotter pin (130). - Tighten stud nut to 128 Nm (94 lbs. ft.). - Align the slot in the stud nut with the hole in the stud. - Bend the pin ends against the nut.
4. Upper ball joint (115) to the knuckle (117).
5. Upper stud nut (129) and new cotter pin (130). - Tighten stud nut (129) to 100 Nm (75 lbs. ft.). - Align the slot in the stud nut with the hole in the stud. - Bend the pin ends against the nut.
6. Washer (1 19) and drive axle nut (1 20). - Tighten nut to 235 Nm (1 73 lbs. ft.).
7. Brake rotor and caliper.
8. Wheel and tire assembly.
9. Repeat procedure on opposite side of vehicle.
PARTS INFORMATION
PART NUMBER MODEL YEAR DESCRIPTION QUANTITY ----------- ---------- ------- -------------------------- ------- 15657212 C 1, 2, 3 1988-89 Lower Control Arm Ball Joint Kit 2 15634942 K 1, 2, 3 1988-90 Lower Control Arm Ball Joint Kit 2 15659518 C/K 1, 2 & C5Z 1988-90 Upper Control Arm Ball Joint Kit 2 15634909 C/K 2 & C6P, 3 1989-90 Upper Control Arm Ball Joint Kit 2 15635534 C/K 3 1988 Upper Control Arm Ball Joint Kit 2 15654867 C/K 1, 2, 3 1988-90 Upper Control Arm Alignment Kit 1
WARRANTY INFORMATION
Dealers should submit a claim on each vehicle completed.
LABOR OPERATION TIME NUMBER DESCRIPTION ALLOWANCE --------- ------------------------------------------- ----------- 1988-89 C-Truck, Replace 4 Ball Joints, 1.5 Hrs T7306 DELETE: For EACH previously installed (bolted) upper all joint .1 Hrs
1988-90 K-Truck, Replace 4 Ball Joints, 3.9 Hrs T7307 DELETE: For EACH previously installed (bolted) ball joint .6 Hrs
1990 C-Truck, Replace Both Upper Ball Joints, 1.1 Hrs T7308 DELETE: For EACH previously installed (bolted) ball joint .1 Hrs
T7311 Check and adjust toe-in alignment .3 Hrs
T7312 1990 ball joint wear check (2 or 4 ball joints) .3 Hrs. When used with T7307 or T7308 .2 Hrs.
T7309 Alignment Parts Kit Supplied to Customer 0.0 Hrs Over the Counter-Use Kit Part Number
Dear GMC Truck Owner:
Some time ago you expressed your confidence in GMC Truck Division through the purchase of one of our GMC Sierra pickup trucks. We appreciate that decision and would like to advise you of a special policy covering the front suspension of your vehicle - specifically, the maintenance-free ball joints and the front wheel alignment procedure.
Your full size GMC pickup truck incorporates maintenance-free front suspension ball joints and a front suspension feature designed to improve the vehicle's ability to maintain front wheel caster/camber alignment. These changes were made in the interest of improving your satisfaction with our product by reducing the amount of required maintenance. We have found that in some cases, however, the actual vehicle maintenance required may not have been reduced.
Ball Joints:
The maintenance-free front suspension ball joints in some of these trucks have experienced contamination. Because of this, we have changed the design of our current production ball joint to a greaseable style ball joint. A contaminated ball joint can cause squeaking while turning and/or more frequent steering input while driving down the road. Contamination could cause a ball joint to wear out and eventually to separate. If any sign of contamination should occur in your vehicle, please have it repaired at your GMC Truck dealer.
Should ball joint contamination cause this condition in your vehicle within 5 years or 100,000 miles of vehicle purchase, whichever occurs first, the maintenance free ball joints will be replaced with greaseable style ball joints free of charge. Greaseable style ball joints should be lubricated at the same interval as the other chassis lubrication fittings on your vehicle. Vehicles requiring ball joint replacement do not necessarily require front wheel alignment. If you have had the ball joints replaced on your vehicle prior to receiving this letter, you can obtain reimbursement for any parts and/or labor charges you may have incurred by providing your dealer with the original paid receipt prior to March 1, 1991. This offer does not apply if the replacement was due to collision damage.
Front Wheel Caster/Camber Alignment Parts Kit: ----------------------------------------------- The front wheel alignment set by the assembly plant will not change and should not need adjustment except in cases where accident or road hazard damage has occurred. Previously, if caster/camber alignment was performed at your expense, you were also charged for the required alignment parts kit. Due to the cost of the parts kit, the charge for a wheel alignment would not be competitive in today's market place. In view of this, GMC Truck has issued a special policy to cover the cost of the caster/camber alignment parts kit but not the installation cost. This kit is included in vehicles currently being produced.
In the event your vehicle requires a caster/camber alignment in the first 5 years or 100,000 miles, whichever occurs first, your GMC Truck dealer will not charge you for the cost of the required parts kit. If you have paid for a caster/camber alignment performed on your vehicle prior to receiving this letter, you can obtain reimbursement for the cost of the parts kit, but not the labor to install it, by providing your dealer with the original paid receipt prior to March 1, 1991.
We are sorry if either of these conditions have caused you any inconvenience; however, we have taken this action in the interest of your continued satisfaction with our products.
FIGURE 1:
BALL JOINT SERVICE REPAIR KIT NOTICE:
NOTICE TO CUSTOMER:
YOUR VEHICLE IS EQUIPPED WITH LUBEABLE BALL JOINTS THAT REQUIRE LUBRICATION AT REGULAR INTERVALS. LUBRICATE FITTINGS AT THE SCHEDULED TIMES LISTED IN SECTION 2A OF THE LIGHT DUTY TRUCK MAINTENANCE SCHEDULE BOOKLET USING WATER RESISTANT EXTREME PRESSURE CHASSIS LUBRICANT WHICH MEETS GM SPECIFICATION 6031M (REF PART NUMBER 1052497 LUBRICANT). CONTINUE TO FILL WITH LUBRICANT UNTIL IT IS PURGED PAST THE SEAL.
General Motors bulletins are intended for use by professional technicians, not a "do-it-yourselfer". They are written to inform those 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 a General Motors dealer servicing your brand of General Motors vehicle for information on whether your vehicle may benefit from the information.
