Product Support Program For Replacing The Front Strut Seals And Related Parts On Certain D20D And D250D Articulated Trucks Caterpillar

Product Support Program For Replacing The Front Strut Seals And Related Parts On Certain D20D And D250D Articulated Trucks

Usage:

@media screen { div.divFooter { display: none; } } @media print { div.divFooter { position: fixed; bottom: 0; right: 0; } }

Caterpillar: Confidential Yellow

NOTE: The information supplied in this service letter may not be valid after the termination date of this program. Do not perform the work outlined in this Service Letter after the termination date without first contacting your Caterpillar product analyst.

NOTE: This Program can only be administered after a failure occurs. The decision whether to apply the Program is made by the dealer. When reporting the repair, use "PS0711" as the Part Number and "7755" as the Group Number. Use "96" as the Warranty Claim Description Code and use "Z" as the SIMS Description Code.

NOTE: If this Program is to be implemented, both cylinders are to be reworked at the same time even if only one is leaking.

Termination Date

February 29, 1996

Problem

In some applications, the front strut seals may become displaced or start leaking on certain D20D and D250D Articulated Trucks.

Affected Product
Model & Identification Number

D20D (9MG1-109)

D250D (6NG1-203)

Parts Needed

2 - 8C5220 Seal

2 - 8C9129 Seal Assembly

2 - 5H6734 Seal-O-Ring

2 - 2J3961 Ring

2 - 4J0520 Seal-O-Ring

2 - 6J7264 Ring

2 - 5K9090 Seal-O-Ring

2 - 2L0043 Ring

2 - 2U9113 Seal

2 - 6U4154 Ring

2 - 6U9505 Seal

2 - 1060636 Cap

Action Required

NOTE: Rework both cylinders even if only one is leaking.

1. Park the machine on level ground. Turn the disconnect switch off. Lower the front suspension.

2. Support the machine with the tools recommended in the Service Manual.

3. Remove the exhaust guards in the area of the right side suspension cylinder for access to the top pin.

4. Ensure that all hydraulic pressure has been released from the system. Disconnect the hydraulic line at the accumulator. Put caps or plugs in the line to keep out dirt or foreign material.

5. Remove the nuts, bolts, pins, and the suspension cylinder. The weight of the cylinder is 32 kg (70 lbs.).

6. Loosen the end cap and separate the rod assembly and piston from the cylinder.

7. Remove the piston from the rod assembly. Remove the existing wear ring and seal from the piston.

8. Remove the existing end cap from the rod assembly along with all associated seals and wear rings.

NOTE: Make sure the proper sized plates from the driver groups are used for installing the seals.

9. Install the new seals and associated parts in the new end cap. Install the new retaining ring to retain the wiper in the end cap. Install the end cap on the rod assembly.

10. Install the piston on the rod assembly. Tighten the bolts to 135 ± 15 N·m

11. Install the new seal and wear ring on the piston.

12. Install the rod assembly and piston into the cylinder. Tighten the end cap to 400 N·m.

13. Install the cylinders. Refer to steps 3 through 5. Use the new o-rings for the hydraulic lines.

14. Bleed the suspension cylinders according to the Service Manual.

15. Adjust the suspension height according to the Service Manual.