Under the Hood – March 20081

Cam Tube Service Kit Installation
Hendrickson released the guidelines for installing the cam tube service kit on compatible axle/beam weldments.

The cam tube service kit can be installed on compatible suspensions from the inboard side of the wheel. It’s not necessary to remove the hub, tire/wheel assembly or brake drum.

If necessary, remove the brake adjuster from the camshaft and remove the existing cam tube. Using #2EP NLGI chassis lube, lightly lubricate the internal seals and bushings on both ends of the new cam tube assembly.

From the inboard side of the suspension beam, slide the new cam tube assembly into the camshaft through the mounting hole in the suspension beam and into the spider. Make sure the end of the cam tube without the decal goes onto the camshaft first. Rotate the cam tube so the grease fitting is accessible (either pointing downward or to the rear) when the drums are installed. (See Figure 1.)

It’s important not to weld or otherwise fasten the cam tube assembly to the spider. The tube assembly simply slip fits into the spider.

Next, arrange the two cam tube brackets back-to-back and slide them onto the end of the cam tube assembly. Slide the brackets onto the cam tube until they contact the suspension beam.

Rotate the cam tube brackets so its holes align with the holes or slots in the suspension beam. If necessary, rotate the cam tube so the grease fitting is accessible when the drums are installed.

Install the four nuts and bolts and tighten them to 35- to 45-ft.-lbs. of torque. Then slide the S-cam journal washer onto the camshaft and seat it against the cam tube assembly.

Using retaining ring pliers, hold open the retaining ring and slide it on the end of the camshaft. Lock the retaining ring into the groove on the camshaft. Slide the second S-cam journal washer onto the camshaft and seat it against the retaining ring.

Lubricate the single, centrally located grease fitting with approximately 4 oz. of #2EP NLGI chassis lube. Add grease until it purges from the cam tube inboard seal. Wipe away excess grease purged from joints to help prevent contaminants from being attracted to the lube points and grease from getting on the brake linings.

Finally, complete the installation by installing the brake adjuster, spline inner washers and spline retaining ring.

Air Intake Grille Loosening
As a result of dimensional variations in the hood opening for the air intake grille on Mack CV model chassis, the retaining clips may not hold the grille in place. The grille may become loose and fall from the hood. Should this occur, the grille should be secured with 3M two-sided tape (3M Part No. 06386) or equivalent.

Install the grille as follows.

• On the backside of the grille, clean the area of the grille between the two retaining clips with alcohol.

• Apply a 6-inch piece of two-sided tape to the grille. (See Figure 2.)
• Use alcohol to clean the area on the edge of the grille opening in the hood where the tape will contact.
• Install the grille into the opening and firmly press until the retaining clips snap into place.

Safety Recalls
The National Highway Traffic Safety Administration has issued the following recalls:

• Certain 2007 and 2008 model year Autocar WX, WXLL and WXR trucks fail to comply with requirements of Part 568, Vehicles Manufactured in Two or More Stages, All Incomplete, Intermediate and Final-Stage Manufacturers of Vehicles Manufactured in Two or More Stages, the gross vehicle weight rating label, as applied, may not be accurate. The label may indicate that the vehicle’s load capacity is higher than the designed weight rating.

  As a result, the vehicle could be overloaded without the vehicle operator’s knowledge. A vehicle in an overloaded condition may be susceptible to component failure that may result in loss of vehicle control, increasing the risk of a crash. Revised GVWR labels need to be applied

• On certain 2008 model year Freightliner Century ST, Columbia and Coronado models the wiper motor ground wire was omitted in a new harness design. The wiper motor may not operate or may function only intermittently. A ground wire needs to be added to the wiper motor harness.
• On certain 2006 to 2008 Freightliner Argosy, Business Class M2, Century ST, Classic, Classic XL, Columbia, Coronado, FLD and FLD 120; Sterling A-Line, Acterra, and L-Line; and Western Star 4900 truck models equipped with Holland Simplex SE or SE II fifth wheels, the latch lever pivot bolt assembly may have been over-tightened. This could distort the pivot bolt spacer sleeve. Corrosion or contaminants in the pivot may cause it to bind and prevent the fifth wheel jaw from latching securely around the trailer king pin.

  The fifth wheel could fail to latch without the driver’s knowledge. When that occurs, the driver could drive away and the trailer could disengage increasing the risk of a crash. The pivot bolt and sleeve need to be replaced with a hex head shoulder bolt and washer.

• The side-view mirrors may have been installed incorrectly on certain 2008 Hino NA6J, NB6J, NC6J, ND8J, NE8J, NJ8J and NV8J models. This could lead to the mirror glass detaching from the mirror housing. If this occurs, the driver may not be able to see traffic approaching from the rear. Defective mirrors must be replaced.
• On certain 2007 and 2008 International 7600 trucks equipped with a split-shaft style power take-off (PTO), the bolts that attach the driveshaft flanges to the split-shaft PTO may loosen and allow the driveshaft to separate from the vehicle.

  Driveshaft separation may occur without warning and could get into the path of other vehicles, causing property damage, personal injury or death.

  The split shaft PTO flange mounting bolts need to be replaced and tightened properly.

• The positive battery cables that supply power from the batteries to the starter may be routed near the engine’s exhaust manifold on certain 2007 and 2008 International MXT models. The excess heat generated by the manifold can cause the cable’s insulation to melt, exposing bare wire.

  This may cause an electrical short or a fire. Battery cables should be inspected, replaced as needed and rerouted away from the engine exhaust manifold.

• On certain 2006 Kenworth T800 emergency vehicles equipped with Cummins CM850 diesel engines, the connecting rods are defective and can result in seizure of the piston pin. A piston pin seizure can result in a mission-disabling engine failure. The defective connecting rods need to be replaced.
• Certain 2005 to 2007 Kidron van trailers fail to comply with the requirements of Federal Motor Vehicle Safety Standard No. 233, Rear Impact Guards. During testing, the slider suspension rail between the rear impact system and the rear support at the rear of the rig system are deformed. The rig system is comprised of the rear impact guard and the trailer support system. The testing procedure was for guard energy absorption and guard strength.

  The purpose of the standard is to reduce the number of deaths and serious injuries that occur when light-duty vehicles collide with the rear end of trailers and semitrailers.

  For vehicles that fail to meet the standard, install supports between the trailer crossmembers above the end of the slider rails.

New Design Piloted
Input Adjuster Released
As of August 2006, all Dana D170, D190 and D590 forward carrier assemblies have been manufactured with a piloted input shaft adjuster and input cover design. The change was made to address premature retainer bolt failures and excessive radial play between the input adjuster and cover.

The piloted design is identified by the portion of threads that have been removed from the adjuster and cover and replaced by a pilot. (See Figure 3.) Additionally, the previous 8mm input adjuster retaining capscrew was replaced with a 12mm stud and jam nut.

To repair the assembly:

• Block the wheels of the vehicle and remove the driveline from the input yoke.

• Measure the input radial play. If it is greater than .010 inch, replace the assembly.
• De-stake the input nut and remove it.
• Use the correct puller to remove the input yoke assembly.
• Remove the power distribution unit cover bolts and the power divider cover assembly.
• Before you install the new piloted cover, clean any old sealant from the carrier surface.
• Apply a 1/8 inch bead of RTV to the carrier. Make sure you go around each bolt hole.
• Install the new piloted cover assembly.
• Turn the adjuster in until it is snug, then back it off one to two notches.
• Measure the end play and set it to .001 inch to .005 inch.
• Install the new retaining stud and make sure it is aligned to an adjuster slot and torques to 20 ft.-lbs.
• Install the retaining stud jam nut and torque it to 65 ft.-lbs.
• Install the new input seal and reinstall the yoke assembly.
• Install the new input nut and torque it to 800 to 1000 ft.-lbs.
• Stake the input nut and reinstall the driveline.

Bussed Electrical Center
With the introduction of the V-Mac IV system in CXP and CTP models, the new electrical system architecture for Mack vehicles uses a bussed electrical center (BEC) and engine power distribution module (EPDM). When diagnosing an electrical system malfunction, you must use the J 35616-4 purple male test lead adapter on the BEC and EPDM terminals.

Do not use a test light or multimeter probe to perform voltage or continuity tests. Doing so will spread the contacts to the point where they will not grip the fuse or relay terminals tightly enough, resulting in additional electrical problems.

If the contacts are spread apart, you will need to replace the BEC and EPDM units. (See Figure 3.)

If the terminals are spread apart as a result of the use of improper test adapters, replacement of the BEC and EPDM units will not be covered under warranty.

Improved Oil Cooler Core
Caterpillar 3126 (Serial No. 1ED1-Up), 3126B (Serial No. 6PZ1-Up and 7JZ1-Up), 3126E (Serial No. LEF1-Up) and C7 (Serial No. FML1-Up and FMM1-Up) engines contain an improved oil cooler.

Teardrop-shaped spacers and cleats for the center support were added between the cooler plates in order to improve the integrity of the oil cooler. Copper plating also has been added to the spacer in order to ensure that adequate brazing occurs.