IFS For Spartan Motorhome Chassis SUBJECT: Service Instructions LIT NO: W&C238 TP DATE: March 2018 REVISION: A TABLE OF CONTENTS Section 1 Introduction . 2 Section 9 Component Replacement . 36 Section 2 Product Description . 2 Fasteners . 36 Air Spring . 36 Section 3 Important Safety Notice . 4 Height Control Valve . 37 Section 4 Parts List . 8 Shock Absorber . 39 Section 5 Special Tools . 10 Hub Assembly . 39 Section 6 Towing Procedure . 13 Hub wheel seal . 40 Section 7 Preventive Maintenance . 14 Bearing Cup . 41 Component Inspection . 14 Hubcap . 42 Lubrication Intervals . 15 Steering Knuckle . 43 Kingpin Lubrication . 15 Kingpin Preparation And Measurement . 44 Tie Rod End Lubrication . 16 Kingpin Bushing Removal . 45 Tie Rod End Inspection . 16 Steering Knuckle Bore Measurement . 46 Tire Inspection . 18 Kingpin Bushing Installation . 46 Shock Absorber Inspection . 20 Kingpin Bushing Reaming . 47 Wheel Bearing End Play Inspection . 22 Kingpin Seal Installation . 48 Upper And Lower Control Arm Bushing Inspection . 22 Steering Knuckle Assembly . 49 Kingpin Bushing Inspection . 23 Upper Control Arm . 50 Steering Knuckle Inspection . 24 Upper Control Arm Bushing Replacement . 52 Section 8 Alignment & Adjustments . 25 Upright Kingpin Assembly . 53 Alignment Definitions . 25 Upright Bearing Replacement . 54 Inspection Prior To Alignment . 27 Lower Control Arm . 55 Front Wheel Alignment . 28 Cradle Gusset . 56 Camber Adjustment . 29 Cradle Assembly . 57 Dual Ride Height Verification . 30 Cradle Belly Plate . 60 Steering Stop . 32 Steering Gear . 61 Wheel Bearing Adjustment . 33 Pitman Arm . 61 Toe Setting . 34 Tie Rod End And Cross Tube . 62 Section 10 Torque Specifications . .. 64 Section 11 Troubleshooting Guide . 66 Section 12 Plumbing Diagram . 68 Section 13 Front Wheel Alignment Specifications . 69 Section 14 Reference Material . 70 Watson & Chalin is a brand of Hendrickson IFS for Spartan Motorhome Chassis SECTION 1 Introduction This publication is intended to acquaint and assist maintenance personnel in the preventive maintenance, service, repair and rebuild of the following W&C equipment as installed on applicable Spartan motorhome chassis: ■ W&C IFS — Independent Front Suspension designed for premium ride and handling for motorhome chassis . NOTE Use only W&C Genuine parts for servicing this suspension system . It is important to read and understand the entire Technical Procedure publication prior to performing any maintenance, service, repair, or rebuild of the product . The information in this publication contains parts lists, safety information, product specifications, features, proper maintenance, service, repair and rebuild instructions for the W&C IFS Suspension . Watson & Chalin Manufacturing Inc . reserves the right to make changes and improvements to its products and publications at any time . Contact W&C Customer Service for information on the latest version of this manual at 1-800-445-0736 (toll-free U .S . and Canada), 1-972-547-6020 (outside U .S . and Canada) or e-mail: WC-Customerservice@watsonsuspensions .com . The latest revision of this publication is also available online at www.watsonsuspensions.com. SECTION 2 Product Description FIGURE 2-1 W&C IFS Capacity: 12,600 pounds Suspension Weight: 1,560 pounds W&C238 TP 2 Introduction IFS for Spartan Motorhome Chassis The W&C IFS delivers superior ride and handling compared to standard front mechanical and air suspen- sions . The short-long arm (SLA) design keeps tires in better contact with the road surface throughout suspension travel by reducing the camber change . The design also reduces bump steer for better handling over rough roads . In addition, the W&C IFS delivers improved steering feel and ride comfort by reducing friction with the introduction of a kingpin design instead of ball joints . ■ Up to 57 degrees of wheel cut for exceptional maneuverability ■ Shock and air spring travel directly proportional to wheel travel, resulting in superior ride and handling Shock Absorbers — W&C IFS utilizes premium shocks that have been tested and tuned specifically for the W&C IFS system . Steering Knuckles — The steering and tie rod arms are integrated for increased strength and reduced weight . The unique steering knuckle packaging delivers a maximum of 57° wheel cut . The two piece knuckle design makes replacing the kingpin bushings easier by eliminating the need to remove the kingpins . Hub and Drum Assembly — The W&C IFS hub and drum assembly provides consistent performance and durability . TECHNICAL NOTES 1 . The W&C IFS is approved for on-highway usage . 2 . The W&C IFS product identification tag is located on the front of the suspension, attached to the cradle gusset; this identifies the complete product assembly and the suspension capacity rating, see Figure 2-2 . FIGURE 2-2 Product Identication Tag Product Description 3 W&C238 TP IFS for Spartan Motorhome Chassis SECTION 3 Important Safety Notice Proper maintenance, service and repair are important to the reliable operation of the suspension . The procedures recommended by W&C and described in this technical publication are methods of performing such maintenance, service and repair . This technical publication should be read carefully to help prevent personal injury and to assure that proper methods are used . Improper maintenance, service or repair may damage the vehicle, cause per- sonal injury, render the vehicle unsafe in operation, or void the manufacturer’s warranty . Failure to follow the safety precautions in this manual can result in personal injury and/or property dam- age . Carefully read and understand all safety related information within this publication, on all decals and in all such materials provided by the vehicle manufacturer before conducting any maintenance, service or repair . ■ EXplanation OF SIGNAL WORDS Hazard “Signal Words” (Danger-Warning-Caution) appear in various locations throughout this publication . Information accented by one of these signal words must be observed to help minimize the risk of personal injury to service personnel, or possibility of improper service methods which may damage the vehicle or render it unsafe . This is the safety alert symbol . It is used to alert you to potential personal injury hazards . Obey all safety messages that follow this symbol to avoid possible injury or death . Additional ‘Notes’ or ‘Service Hints’ are utilized to emphasize areas of procedural importance and provide suggestions for ease of repair . The following definitions indicate the use of these signal words as they appear throughout the publication . DANGER Indicates an imminentlY haZardous situation which, IF not avoided, WILL result IN serious INJURY OR DEATH . WARNING Indicates A POTENTIAL HAZARDOUS situation WHICH, IF NOT avoided, CAN result IN SERIOUS INJURY OR DEATH . CAUTION Indicates A POTENTIAL HAZARDOUS situation WHICH, IF NOT avoided, MAY result in minor OR moderate INJURY, OR propertY DAMAGE . NOTE An operating procedure, practice condition, etc . which is essential to emphasize . SERVICE HINT A helpful suggestion, which will make the servicing being performed a little easier and/or faster . Also note that particular service operations may require the use of special tools designed for specific purposes . These special tools can be found in the Special Tools Section of this publication . The torque symbol alerts you to tighten fasteners to a specified torque value . Refer to Torque Specifications Section of this publication . W&C238 TP 4 Important Safety Notice IFS for Spartan Motorhome Chassis ■ SAFETY PRECAUTIONS WARNING FASTENERS DISCARD USED FASTENERS . ALWAYS USE NEW FASTENERS TO COMPLETE A REPAIR . FAILURE TO DO SO COULD RESULT IN FAILURE OF THE PART, OR MATING COMPONENTS, ADVERSE VEHICLE HANDLING, PERSONAL INJURY, OR PROPERTY DAMAGE . LOOSE OR OVER TORQUED FASTENERS CAN CAUSE COMPONENT DAMAGE, Adverse vehicle handling, PROPERTY DAMAGE, OR SEVERE PERSONAL INJURY . MAINTAIN CORRECT TORQUE VALUE AT ALL TIMES . CHECK TORQUE VALUES ON A REGULAR BASIS AS SPECIFIED, USING A REGULARLY CALIBRATED TORQUE WRENCH . TORQUE VALUES SPECIFIED IN THIS TECHNICAL PUBLICATION ARE FOR W&C SUPPLIED FASTENERS ONLY . IF NON-W&C FASTENERS ARE USED, FOLLOW TORQUE SPECIFICATION LISTED IN THE VEHICLE MANUFACTURER’S SERVICE MANUAL . WARNING TORCH/WELDING DO NOT USE A CUTTING TORCH TO REMOVE ANY FASTENERS . THE USE OF HEAT ON SUSPENSION COMPONENTS WILL ADVERSELY AFFECT THE STRENGTH OF THESE PARTS . A COMPONENT DAMAGED IN THIS MANNER can RESULT IN loss of vehicle control AND POSSIBLE PERSONAL INJURY OR PROPERTY DAMAGE . EXERCISE EXTREME CARE WHEN HANDLING OR PERFORMING MAINTENANCE IN THE AREA OF THE SUSPENSION SYSTEM . DO NOT CONNECT ARC WELDING GROUND LINE TO ANY COMPONENTS ON THE suspension SYSTEM . DO NOT STRIKE AN ARC WITH THE ELECTRODE ON THE suspension SYSTEM . DO NOT USE HEAT NEAR THE SUSPENSION SYSTEM . DO NOT NICK OR GOUGE THE SUSPENSION SYSTEM . SUCH IMPROPER ACTIONS CAN DAMAGE THE SUSPENSION SYstem, AND CAN CAUSE ADVERSE VEHICLE HANDLING AND POSSIBLE PERSONAL INJURY OR PROPERTY DAMAGE . WARNING AIR SPRINGS AIR SPRING ASSEMBLIES MUST BE DEFLATED PRIOR TO LOOSENING ANY SUSPENSION COMPONENTS . UNRESTRICTED AIR SPRING ASSEMBLIES CAN VIOLENTLY SHIFT . DO NOT INFLATE AIR SPRING ASSEMBLIES WHEN THEY ARE UNRESTRICTED . AIR SPRING ASSEMBLIES MUST BE RESTRICTED BY SUSPENSION OR OTHER ADEQUATE STRUCTURE . DO NOT INFLATE BEYOND PRESSURES RECOMMENDED BY AIR SPRING MANUFACTURER, CONTACT W&C CUSTOMER SERVICES FOR DETAILS . IMPROPER USE OR OVER INFLATION MAY CAUSE AIR SPRING ASSEMBLIES