Severe-service Top Pad Bolt Kit
The following information is to assist you with installing the Hendrickson severe-service top pad bolt kit, No. 58821-026 on Primaax 230/460/690 rear air suspensions.
The procedure to install the severe-service top pad kit is done on one top pad connection at a time. All other suspension components are to remain connected during service. Failure to do so can cause the axle to rotate or shift, possibly damaging components or personnel.
- Place the vehicle on a level floor.
- Chock the wheels.
- Support the frame of the vehicle at ride height. Air spring assemblies must be deflated prior to installing the kits.
- Disconnect the height control linkage assembly from the height control valve arm. Lower the leveling valve arm to exhaust the air in the springs and deflate the rear suspension.
- Remove the existing fasteners connecting the longitudinal torque rod to the top pad and discard.
- Prior to assembly, verify the new M24 bolt will pass through the existing top pad and inner metal of the torque rod bushing (see figure 1).
- If the fastener will not pass through the parts, enlarge the holes to 15⁄16-inches. To access the top pad hole, you may have to disassemble the clamp group.
- Assemble the new severe-service fastener through the top pad and longitudinal torque rod. Tighten the locknut to 400 +/- 25 ft.-lbs. (see figure 2).
- Inflate the suspension by connecting the height control valve linkage to the height control valve arm. Verify the air springs inflate uniformly without binding.
- Remove the frame supports.
- Remove the wheel chocks.
- Verify proper ride height adjustment.
Controlling Contamination
According to Caterpillar, the way equipment is maintained can contribute to contamination problems, especially in hydraulic systems. Cat offers these tips to help control contamination:
- Change oil filters regularly and carefully. Because oil filters contain contaminants, it is important to remove them carefully. Proper removal ensures that contaminants do not re-enter a system. It also is important to keep new filters free of contaminants by leaving them in their packaging until you are ready to use them.
- Change air filters only as shown by the service indicator. The Cat air filter service indicator provides a gradual reading of the air filter’s condition. It will indicate when the filter needs to be replaced.
- Use the proper filter. Filters that do not meet the efficiency requirements of your customers’ needs can allow dirt to circulate within the systems. Make sure you install the proper filter for the vehicle’s application.
- Use high-efficiency filters after the system has been open. Cat high-efficiency filters have ultra-fine media that trap even tiny contaminants. Installing these filters after hydraulic or drivetrain systems have been open for maintenance or repair can help eliminate any contaminants that may have entered the system.
- Change oil regularly and properly. Drain oil when it is warm and agitated (contaminants are stirred up so more are removed during the oil change).
- Use tight-fitting drum covers. Airborne particles and water can enter oil drums. Fitting drums with protective covers can help eliminate this problem. Always store drums indoors and on their sides to reduce the chances of contamination.
Safety Recalls
The National Highway Traffic Safety Administration (NHTSA) has issued the following recalls:
- Champion is recalling 20 2008 model year buses built on Freightliner chassis and equipped with Bendix SR-7 spring brake modulating valves. The internal rubber check valve may leak causing a delay in the application of the spring brakes to park the vehicle after the operator pulls the dash valve button. This could cause a delay or failure in applying the parking brakes, which could result in a vehicle roll away, increasing the risk of a crash.
- Blue Bird is recalling 45 2008-2009 model year Micro-Bird school buses manufactured from October 1, 2007, through January 28, 2008, mounted on General Motors chassis with optional 3016-05 or 30117-05 LED rear turn signals. These buses fail to comply with the flash rate requirements of Federal Motor Vehicle Safety Standard No. 108. The lights operate at approximately 180 flashes per minute and the standard requirement is 60 to 120 flashes per minute. To correct the defect a resistor needs to be installed in the turn signal circuit which will bring the LED rear turn signal flash rate into compliance with the standard.
- Motor Coach is recalling 24 model year 2008 D4505, D4500 and D4000ISTV coaches equipped with TRW Model TAS85 steering gears. These steering gears contain potentially defective sector shafts with an incorrect gear tooth, which may interfere with the rack-piston teeth, resulting in a sticking or binding condition.
- Paccar is recalling 6,169 2008 model year Kenworth T330, T660, T800, T2000, W900 and C500 vehicles and 2008-2009 model year Peterbilts 365, 367, 384, 387, 388, 389 and 389 kits. Certain door latch assemblies on these vehicles fail to conform to the requirements of Federal Motor Vehicle Safety Standard No. 206. The rotor in some of these door latch assemblies did not receive the proper heat treatment and may be soft. In the event of a crash, force could cause the rotor to crack and the door would not have primary or secondary closing security, which could possibly lead to injury of the vehicle occupant. Door latches that are found to be defective will be replaced.
Viscous Fan Drive Fault
On certain Mack model chassis equipped with either an MP7 (U.S. 2007 emission compliant) or MP8 engine, a driver may experience an electronically controlled viscous fan drive full-time engagement (until the ignition key is cycled off and on), and an MID 128, SID 33, FMI 4 fault code may be logged.
Generally there are no cooling system problems associated with the full-time fan engagement, nor with the fault code.
To correct this condition, a new engine dataset has been developed and was implemented into production as follows:
- Vehicles equipped with MP7 (U.S. 2007 emission compliant) engines – engine manufacture date November 19, 2007, and later beginning with Serial No. 512456.
- Vehicles equipped with MP8 engines – engine manufacture date October 15, 2007, and later beginning with Serial No. 905617.
If you encounter full-time fan engagement and a logged MID 218, SID 33, FMI 4 fault code on a vehicle having an engine manufactured prior to the above dates, reprogram the EECU with the current software.
Loss of Power to Sleeper
On Mack CXU, CHU and CXP model chassis equipped with a sleeper and a Hi-line instrument cluster, there is an integrated low-voltage disconnect option, which disconnects power to the sleeper if battery power should fall below 12 volts.
This function is controlled by the low-voltage disconnect (LVD) relay, which is located under the left-hand side of the sleeper bunk. When battery power is restored above 12 volts, the dash cluster signals the LVD relay to restore power to the sleeper.
In extreme cases, such as when battery power drops below 9 volts, the instrument cluster will shut down. When battery power returns to 12 volts, the cluster will reset. At this point, however, the instrument cluster has lost track of the relay status and does not signal the relay to restore power to the sleeper. Upgrading the software of the Hi-line instrument cluster will correct this condition.
If a customer complains of no power to the sleeper, use VCADS to program MID 140.
