Technical Service BULLETIN

Transcription

1 Technical Service BULLETIN December 24, Sienna ST STEERING Introduction To provide a smoother steering return feeling, the steering rack guide has been changed. Applicable Vehicles 1998 through 2000 model year Sienna Parts Information PREVIOUS PART NUMBER CURRENT PART NUMBER PART NAME QUANTITY Rack Guide Sub Assembly 1 Required Tools & Material TOOL PART NO. TOOLS & MATERIALS QUANTITY Steering Worm Bearing Adjusting Socket Variable Open Wrench Hex Wrench Handle Three Bond 1344 Loctite 242 (or equivalent) 1 Warranty Information Perform repairs as necessary per the listed repair procedure. Submit warranty claims for actual repairs performed using the following operation codes. OP CODE DESCRIPTION TIME OPN T1 T R & R Power Steering Rack Guide and/or Rack Guide Seat Applicable Warranty*: This repair is covered under the Toyota Basic Warranty. This warranty is in effect for 36 months or 36,000 miles, whichever occurs first, from the vehicle s in-service date. * Warranty application is limited to correction of a problem based upon a customer s specific complaint. Toyota Supports ASE Certification

2 STEERING RACK GUIDE INSTALLATION PROCEDURE 1. Remove Power Steering Gear. Refer to appropriate Repair Manual RM594U, RM657U, or RM701U. See page SR 35 for procedures. a. Mark the outer tie rod ends/tie rod lock nut and the inner tie rod prior to removing the steering gear. b. Mark the intermediate shaft to the steering rack pinion shaft (control valve shaft) prior to removing the steering gear. c. Disconnect the clamp plate attached on the steering gear. d. Disconnect the steering pressure lines from the steering gear. 2. Replace Steering Rack Guide. a. Using ( ), remove the rack guide spring cap lock nut. Rack Guide Spring Cap Lock Nut Using ( ) in the direction shown in the illustration. b. Remove the rack guide spring cap, rack guide spring and rack guide sub assembly. 1. Using ( ) and a Box End Wrench (21mm), remove the cap. 2. Remove the spring and rack guide. c. Install a new rack guide sub assembly. Reuse original rack guide spring and rack guide spring cap.

3 1. Apply approximately 2 grams of chassis grease to the surface of the new rack guide which will be in contact with the steering rack. 2. Install the rack guide and spring. 3. Apply sealant to 2 or 3 screw threads of the cap. Sealant: P/N , THREE BOND 1344, LOCTITE 242 or equivalent. 4. Temporarily install the cap. d. Adjust total preload. 1. Using ( ) (21mm), torque the rack guide spring cap. 12 Torque: 25 N m (250 kgf cm, 18 ft lbf) 2. Using ( ) (21mm), loosen the cap 12. 5mm Loosen 12 (approximately 5mm around cap) 3. Using ( ), cycle steering rack from lock to lock 2 times. This will configure the rack guide seat to the steering rack. 4. Return rack to center position (approximately 1.4 turns from lock).

4 5. Using ( ) (21mm), loosen the cap until the rack guide spring is not functioning. Hexagon Wrench 6. Using s ( & ), a Torque Wrench and a Box End Wrench (21mm), tighten the cap until the preload is within specification. Rack Guide Spring Cap Preload (turning): N m (8 14 kgf cm, in lbf) IMPORTANT: When checking the steering rack total preload: Measure the torque during the rotation of the steering rack pinion shaft (control valve shaft), NOT the initial torque to start rack movement. Measure the torque at the steering rack center point, making sure that there is smooth rotation from lock to lock. Measure the torque in both directions of the rotation and average the readings to arrive at a total reading. CAUTION: Total preload is critical to steering feel. It is important that this procedure be followed accurately. e. Install the rack guide spring cap lock nut. 1. Clean the threads of the lock nut.apply sealant to the threads of the lock nut. Sealant: P/N , THREE BOND 1344, LOCTITE 242 or equivalent. 3. Install the Lock Nut.

5 4. Using ( ) and a Box End Wrench (21mm), hold the Rack Guide Spring Cap. 5. Tighten the Lock Nut using ( ) and a Torque Wrench. Rack Guide Spring Cap Lock Nut Fulcrum length Hexagon Wrench Torque: 50 N m (513 kgf cm, 37 ft lbf) Use in the direction shown in the illustration. IMPORTANT: To obtain the correct torque when using , use a torque wrench with a fulcrum length of 345 mm (13.58 in.). 6. Confirm total preload to ensure it is within specification. Preload (turning): N m (8 14 kgf cm, in lbf) 3. Reinstall Power Steering Gear As Described In Repair Manual (See page SR 50.) Confirm that the power steering fluid level is full. 4. Check Vehicle Alignment (toe only) Set toe specification in the Repair Manual (See page SA 4). 5. Road Test Vehicle.