A comprehensive pull and drift diagnostic procedure has been developed to assist technicians in resolving pull or drift concerns.

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1 TSB 98-5A-39 BRAKES - PULL OR DRIFT - DIAGNOSTIC AND SERVICE PROCEDURES - 4X2 AND 4X4 MODELS STEERING - PULL OR DRIFT - DIAGNOSTIC AND SERVICE PROCEDURES - 4X2 AND 4X4 MODELS Publication Date: MARCH 18, 1998 LIGHT TRUCK: BRONCO, E-150, F-150 ISSUE: A comprehensive pull and drift diagnostic procedure has been developed to assist technicians in resolving pull or drift concerns. ACTION: Use the following Service Procedure, guided by the flowchart in Figure 3, to resolve drift and pull concerns. Figure 3 - Article 98-5A-39 IT IS POSSIBLE THAT THE VEHICLE MAY HAVE MULTIPLE SYMPTOMS. THEREFORE, IT IS NECESSARY TO USE THE FLOWCHART IN FIGURE 3.

2 DEFINITIONS PERTINENT TO THIS TSB ARTICLE: BRAKE PULL: WHEN DRIVING ON A FLAT, STRAIGHT ROAD (WITHOUT A CROWN), THE VEHICLE ALTERS FROM A STRAIGHT COURSE DURING APPLICATION OF BRAKES WITH TORQUE FELT IN STEERING WHEEL RECESSION STEER: WHEN DRIVING ON A FLAT, STRAIGHT ROAD (WITHOUT A CROWN), THE VEHICLE DRIFTS RIGHT OR LEFT DURING APPLICATION OF BRAKES WITH NO TORQUE FELT IN STEERING WHEEL STEADY-STATE DRIFT: WHEN DRIVING ON A FLAT, STRAIGHT ROAD (WITHOUT A CROWN), THE VEHICLE ALTERS FROM A STRAIGHT COURSE WITHOUT APPLYING THE BRAKES THE CUSTOMER ROAD TEST Test drive the vehicle with the customer to understand the pull or drift concern. Sometimes they may mistakenly call a clear vision concern a pull or drift concern because the steering wheel is not straight. The road test should be done on a flat, straight road (with no crown) and should be done in both directions to account for wind Tire pressure should be checked and adjusted, if necessary On vehicles with automatic locking hubs, it is necessary to drive 6m (20 ft) forward and then 3m (10 ft) backward to unlock the hubs THIS TSB ARTICLE SHOULD BE READ COMPLETELY BEFORE PERFORMING DIAGNOSTICS OR REPAIRS. DIAGNOSTIC PROCEDURE #1 - STEERING GEAR MESHLOAD MESHLOAD CHECK/RESET If the steering system exhibits on-center free play, or in general displays a vague on-center feel or lash, this could contribute to reduced straight-line stability and a customer perception of drift or pull. In these cases, a fall-off in factory-set levels of steering gear meshload may be the cause. Setting meshload too high may result in customer dissatisfaction with higher efforts and overall steering feel. ADJUSTMENT PROCEDURE Adjust the steering wheel to be at center position. Disconnect the battery. Raise the vehicle and disconnect the steering gear sector shaft arm from the steering gear sector shaft using Pitman Arm Puller (T64P-3590-F). Lower the vehicle. Remove the steering wheel hub cover. REFER TO THE APPROPRIATE SERVICE MANUAL, SECTION 11-04, FOR REMOVAL AND INSTALLATION OF THE AIR BAG. 6. Attach a pound-inch torque wrench to the steering wheel nut. USE OF A DIAL-TYPE POUND-INCH TORQUE WRENCH IS RECOMMENDED. DO NOT USE A N-m (LB-FT) OR CLICKER-TYPE TORQUE WRENCH Determine the torque required to rotate the steering gear sector shaft back and forth across the center position (±90 ). 2. Loosen the adjuster locknut and turn the sector shaft adjuster screw until the total on-center torque reading is N-m (15-17 lb-in). 3. Hold the sector shaft screw in place and tighten the locknut to N-m (34-45 lb-ft). Recheck the steering gear on-center torque readings and reinstall the steering wheel hub cover. Raise the vehicle and reconnect the steering gear sector shaft arm. Lower the vehicle and reconnect the battery. WHEN THE BATTERY HAS BEEN DISCONNECTED AND RECONNECTED, SOME ABNORMAL DRIVE SYMPTOMS MAY OCCUR WHILE THE POWERTRAIN CONTROL MODULE (PCM) RELEARNS ITS ADAPTIVE STRATEGY. THE VEHICLE MAY NEED TO BE DRIVEN 16 KM (10 MILES) OR MORE TO RELEARN THE STRATEGY. 10. Perform road test, referring to the "Overview of Repair Procedure" flowchart in Figure 3 for further procedure.

3 TECHNICIAN'S ROAD TEST RESULT ACTION (A) Maintain a steady speed of km/h (50-55 mph). DO NOT BRAKE. Is there a steady-state drif t? ** YES NO Perform Diagnostic Procedure #2, Caster Split, then proceed to Road Test (B). Skip to Road Test (B). (B) In a safe clear area, while firmly holding the steering wheel, apply the brakes moderately hard but not to the point of engaging RABS or four wheel ABS. Does the vehicle's heading alter during brake application? YES NO Perform Diagnostic Procedure #3, Recession Steer And Diagnostic Procedure #4, Brake Imbalance. Return vehicle to customer. ** Be sure front hubs are unlocked (if equipped). For proper steady-state drift evaluation, accelerate and decelerate the vehicle using ENGINE BRAKING ONLY. DIAGNOSTIC PROCEDURE #2 - ALIGNMENT Wheel Alignment - Measure the front wheel alignment. For out-of-specification vehicles, align to the " Optimum Light Truck Alignment Service Specifications" found in the following two charts. DIAGNOSTIC PROCEDURE #1 MUST BE PERFORMED BEFORE ALIGNMENT. TEST DRIVE VEHICLE AFTER ALIGNMENT IS PERFORMED OPTIMUM LIGHT TRUCK ALIGNMENT SERVICE SPECIFICATIONS MODEL CAMBER AVERAGE* CASTER AVERAGE (minimum) CASTER AVERAGE** (maximum) F-150 (4X2) 0.25 (±0.5 ) 2 6 Lightning 0 (±0.5 ) 2 6 E-150 (4X2) 0.25 (±0.5 ) F-150 (4X4) 0.25 (±0.5 ) 2 6 Bronco 0.25 (±0.5 ) OPTIMUM LIGHT TRUCK ALIGNMENT SERVICE SPECIFICATIONS MODEL TOTAL TOE**** (optimum) CAMBER SPLIT (optimum) CASTER SPLIT*** (optimum) F-150 (4X2) 0.06 (±0.25 ) 0 (±0.5 ) -0.5 (±0.5 ) Lighting 0.06 (±0.25 ) 0 (±0.5 ) -0.4 (±0.5 ) E-150 (4X2) 0.06 (±0.25 ) 0 (±0.5 ) -1.0 (±0.5 ) F-150 (4X4) 0.06 (±0.25 ) 0 (±0.5 ) 0 (±0.5 ) Bronco 0.06 (±0.25 ) 0 (±0.5 ) 0 (±0.5 ) * CAMBER AVERAGE is the sum of LH camber plus RH camber divided by two (2). Vehicles set to this

4 specification, as measured with the vehicle loaded to normal loading conditions, will result in optimum tire wear. ** CASTER AVERAGE is the sum of LH caster plus RH caster divided by two (2). These are not recommended values for settings. They are only maximum and minimum limitations. *** CASTER SPLIT is LH caster minus RH caster. ****TOTAL TOE is the sum of LH toe plus RH toe angles. Vehicles which exceed the maximum average caster value shown above may result in shimmy concerns Vehicles operated below the minimum average caster value shown may result in wander and poor steering returnability concerns. If appropriate, reset no minal LH/RH caster to the high end of the specification DIAGNOSTIC PROCEDURE #3 - RECESSION STEER (F-SERIES AND BRONCO ONLY - FOR ECONOLINE, SKIP TO DIAGNOSTIC PROCEDURE #4) REMOVAL AND REPLACEMENT REFER TO THE F-SERIES/BRONCO SERVICE MANUAL, SECTION 04-01A (4X2) OR 04-01B (4X4), FOR REMOVAL AND REPLACEMENT OF THE FOLLOWING COMPONENTS. F-Series Only Built Before 3/15/95 1. Replace the right side radius arm bracket fasteners. THE SPECIFIED FASTENERS AND TORQUE REQUIREMENTS MUST BE USED. SEE FIGURE 2 FOR A DESCRIPTION OF PARTS CONTAINED IN THE RIGHT SIDE RADIUS ARM BRACKET KIT (E8TZ-3L095-A). REPLACE ONE (1) RIVET AT A TIME TO MAINTAIN BRACKET LOCATION.

5 Figure 2 - Article 98-5A Start with rivet #1 (Figure 1). Drill a 3.175mm (1/8") hole through the middle of the rivet.

6 Figure 1 - Article 98-5A Drill the same hole with an 11/32" drill. 3. Use an air chisel to remove the rivet head. 4. Drive the rivet out with a punch. 5. Line ream the #1 rivet (Figure 1) hole in the frame web to a 12.7mm (1/2") diameter. 6. Install a 1/2" Grade 8 bolt. The bolt head must be on the inboard side of the frame. Install a 1/2" hardened washer on the outside of the bracket. Install the nut and tighten to 142 N-m (105 lb-ft). Refer to Figure Remove the #2 rivet (Figure 1) using Steps a through d. 8. Line ream the #2 rivet (Figure 1) hole on the frame flange to a mm (9/16") diameter. 9. Install a 9/16" Grade 8 bolt. The bolt head must be on the inboard side of the frame flange. Install a 9/16" hardened washer on the outboard side of the bracket. Install the nut and tighten to 190 N-m (140 lb-ft). Refer to Figure Repeat Steps h and i for the #3 (Figure 1) rivet. BE SURE TORQUE SPECIFICATIONS ARE FOLLOWED Replace the LH (driver side) radius arm bushing cupped front retainer with the flat front Retainer (F2TZ- 3B186-A). Replace the LH (driver side) radius arm front pivot bushing with the new Bushing (F2TZ-3B203-A). It is yellow in color with "LEFT HAND ONLY" molded in the front face. Replace the RH (passenger side) radius arm front pivot bushing with a new Bushing (F1TZ-3B203-A). REUSE THE ORIGINAL NYLON REAR BUSHING SPACER UNLESS EXCESSIVE WEAR IS FOUND. IF NYLON REAR BUSHING SPACER REPLACEMENT IS NECESSARY, REPLACE WITH E5TZ-3B244-A. TIGHTEN BOTH THE LEFT AND RIGHT HAND RADIUS ARM NUTS TO THE SPECIFIED TORQUE, N-m ( LB-FT). All Bronco And F-Series Built On Or After 3/15/95 Check the torque on the nuts securing the RH radius arm pivot bracket. 1. Check and adjust, if required, the torque of the nuts securing the RH radius arm pivot bracket to the frame flange. The correct torque is 91 N-m (67 lb-ft). 2. Check and adjust, if necessary, the torque of the nuts securing the RH radius arm pivot bracket to the frame web (side rail). The correct torque is 133 N-m (98 lb-ft). DIAGNOSTIC PROCEDURE #4 - BRAKE IMBALANCE 1. Check the rear brakes. Remove the rear wheels and brake drums. Check the cage diameter using the Brake Adjustment Gauge (D81L-1103-A, or equivalent). If either side is out-of-specification, check for proper function of the adjusting mechanism and repair or replace as required.

7 REFER TO TSB ARTICLE 98-5A-41 FOR ON-VEHICLE ROTOR MACHINING INFORMATION AND ITS REFERENCE TO INSUFFICIENT TURNING MATERIAL. 2. Resurface (turn) both front rotors on-vehicle. CAUTION: BE SURE LUBRICANT DOES NOT GET ON THE ROTORS, LININGS, OR CALIPER PISTON BOOTS. 3. Inspect and clean any corrosion buildup under and around the knuckle rail and spring clips. Lubricate between knuckle rail and spring clips with Silicone Brake Caliper Grease and Dielectric Compound (D7AZ-19A331-A). 4. Install the new front matched Brake Linings (F5TZ-2001-BC). Be sure the last three (3) digits of the left inner pad are matched with the last three (3) digits of the right inner pad. Similarly, be sure the last three (3) digits of the left outer pad are matched with the last three (3) digits of the right outer pad. For example, a typical code on the edge of a pad would be 5196 BX NC EE 123 LA. 123 must be matched between the left and right pads. 5. Lightly apply Silicone Brake Caliper Grease and Dielectric Compound where spring clip contacts the brake pad. There are four (4) lubrication points for each brake pad: Upper pad slide area Upper anti-rotation ear Lower pad slide area Lower anti-rotation ear REFER TO THE APPROPRIATE SERVICE MANUAL, SECTION 06-03, FOR DETAILS. EVENLY TIGHTEN THE FIVE (5) LUG NUTS (1/2"-20) IN A CRISSCROSS-TYPE PATTERN TO 140 ±40 N-m (103 ±30 LB-FT). USE DARK BROWN ACCUTORQ SOCKET AS DESCRIBED IN TSB ARTICLE Advise the customer of the "Breaking Your Vehicle In" section in the front of their Owner Guide. This section recommends that the customer avoid sudden stops due to new brake linings. It suggests that the following steps be taken: Watch traffic carefully so that you can anticipate when to stop Begin braking well in advance Apply the brakes gradually The break-in period for new brake linings lasts for 160 km (100 miles) of city driving or 1,600 km (1,000 miles) of highway driving. PART NUMBER PART NAME E8TZ-3L095-A Right Side Radius Arm Bracket Hardware (Kit) F2TZ-3B186-A Radius Arm Bushing Retainer F2TZ-3B203-A Front Pivot Bushing - LH F1TZ-3B203-A Front Pivot Bushing - RH E5TZ-3B244-A Rear Bushing Spacer D7AZ-19A331-A Silicone Brake Caliper Grease And Dielectric Compound F5TZ-2001-BC Front Brake Lining Kit OTHER APPLICABLE ARTICLES: , , 98-5A-13, 98-5A-41 SUPERSEDES: WARRANTY STATUS: Eligible Under The Provisions Of Bumper To Bumper Warranty Coverage

8 OPERATION DESCRIPTION TIME 985A39A Procedure #1 - Steering Gear Meshload 0.6 Hr. 985A39B Procedure #2 - Alignment - F-150, Bronco A39C Procedure #2 - Alignment - E A39D Procedure #3 - Recession Steer - F-150 Built Before 3/15/ A39E Procedure #3 - Recession Steer - F-150, Bronco Built On Or After 3/15/ Hr. 985A39F Procedure #4 - Brake Imbalance - Bronco And F-150 (4X4) - Includes Time To Check Rear Brakes, Resurface Rotors On-Vehicle And Install New Linings A39G DEALER CODING Procedure #4 - Brake Imbalance - E-150 And F-150 (4X2) - Includes Time To Check Rear Brakes, Resurface Rotors On-Vehicle And Install New Linings BASIC PART NO. CONDITION CODE OASIS CODES: , , Copyright 1998 Ford Motor Company

STEERING SHIMMY DIAGNOSTIC PROCEDURE Article No. 4X2 AND 4X4 VEHICLES

STEERING SHIMMY DIAGNOSTIC PROCEDURE Article No. 4X2 AND 4X4 VEHICLES 98-15-8 FORD: 1988-1997 F SUPER DUTY, F-250 HD, F-350 This TSB article is being republished in its entirety to include the latest level