Rear Tires - Unusual Wear Patterns
TS85-114October 23, 1985
Wheel & Tire
REAR TIRE WEAR, SENTRA AND PULSAR
APPLIED MODEL:
MODEL PRODUCTION DATE
Sentra 09/83 - on
Pulsar 12/83 - on
SERVICE INFORMATION
Some Sentra and Pulsar models may exhibit unusual rear tire wear patterns. There are two different types of tire wear (Type A and Type B). An incident vehicle may exhibit either or both types.
Type A
Type A tire wear is best described as smooth, even wear on the outside shoulder of the tire, and the wear may be unequal on right and left tires. The following factors will increase the rate of Type A tire wear:
1. Low or uneven tire pressure.
2. Abrasive road surfaces.
3. Frequent high vehicle loads.
4. Rear tow-in near the specification limit.
Type B
Type B rear tire wear is best described as a diagonal scrub pattern with cupping. This irregular rear tire wear is caused by a combination of the following:
1. Excessive rear tire/wheel imbalance or tire non-uniformity.
2. Frequent high vehicle loads.
3. Rear toe-in near the specification limit.
Use the following Parts Information and Service Procedures to reduce the rate of rear tire wear on incident vehicles. Tires with excessive wear should be replaced as part of the procedure.
PARTS INFORMATION
FORMER COUNTERMEASURE
PART DESCRIPTION QTY PART NUMBER PART NUMBER COMMENT
Rear spring (Sedan) 2 55020-32A05 55020-32A06 5mm longer
Rear spring (Wagon) 2 55020-32A07 55020-32A09 19mm longer
Rear control arm (RH) 1 55501-03A11 55501-02A11 Contains stiffer
Rear control arm (LH) 1 55502-03A11 55502-02A11 bushings
SERVICE PROCEDURE
Use the following chart to determine which steps to perform for the incident vehicle.
MODEL
Sentra Wagon Performsteps 1, 2, 3 and 4 only
Sentra Sedan Perform steps 2, 3, 4 and 5 only
Sentra Coupe Perform steps 3, 4 and .5 only
& Pulsar
Step 1. Sentra Wagon: Refer to page RA-5 of the 1986 Sentra Service Manual
and replace both lower control arms with countermeasure parts.
Step 2. Sentra Sedan and Wagon: Replace rear coil springs with
countermeasure parts.
Step 3. All models: Balance both rear tire/wheel assemblies.
Step 4. All models: Adjust rear suspension to maximum toe-out position as
follows:
a. Drive the vehicle onto a ramp-type hoist that supports the vehicle by its tires.
b. Loosen the rear lower control arm bolts.
c. Pull both rear control arms inward toward the center of the vehicle by fastening a power puller (also known as a come-along) around the lower shock absorber mounts.
d. While maintaining tension of less than 100 lbs. on the lower control arms, torque the rear lower control arm bolts to 43-51 ft/lbs.
e. Remove the power puller.
Perform Step 5 on Sentra Sedans, Coupes and Pulsar vehicles only if they exhibit Type B rear tire wear:
Step 5. Road test the vehicle and check for seat/floor pan vibration and rear spindle fore and aft movement at highway speeds (50-65 mph). This is best detected by having an observer follow the incident vehicle in a separate vehicle and watch the rear wheels while traveling at highway speeds. If the incident vehicle exhibits rear spindle fore and after vibration after adjusting rear toe, install the countermeasure rear control arms with stiffer bushings and repeat Step 4. The owner should be made aware that this change will slightly decrease ride comfort.
WARRANTY INFORMATION
CS PNC CT
2V 55501 34
Use the chart below to determine the proper OP CODE and FLAT RATE.
MODEL STEPS OP CODE FLAT RATE
Sentra Wagon 1, 2, 3, 4 LJ99AA 3.8
Sentra Sedan 2, 3, 4 LJ99AB 1.8
2, 3, 4, 5 LJ99AC 4.3
Sentra Coupe 3, 4 LJ99AD 1.1
and Pulsar 3, 4, 5 LJ99AE 4.3