2001/12/24 Caterpillar

Articulated Truck

D400E Series II (S/N: 8PS1-UP)

Ejector Truck

D400E Series II Ejector (S/N: APF1-UP)

Service Magazine, SEPD0610, 24, December 2001, "A New Housing for the Interaxle Differential Lock Improves the Capability of the Lock". The new housing that was referenced in the above Service Magazine article has been canceled and replaced by an improved housing. Disregard the previous article and use the following information.

Reference: Disassembly and Assembly, RENR1511, "D400E Series II Power Train"

Description Of Change: The housing for the interaxle differential lock in the output transfer gear of the above machines has been changed twice.

Illustration 1	g00837539

The original 135-3222 Housing was canceled and replaced by 174-8797 Housing and two new 174-9593 Seal Rings. The 174-8797 Housing gave a greater clearance with the other internal components. This improvement offered an increase in the service life of the components. The improvement allowed the interaxle differential lock to act with greater capability. The two new 174-9593 Seal Rings (2) were also required because of the greater clearance.

This change was effective with D400E Series II (S/N: 8PS1059-UP). The change was never installed on D400E Series II Ejector (S/N: APF) machines in the factory. This change might have been installed to machines in the field.

The 174-8797 Housing has now been canceled and replaced with 224-2997 Housing. The 224-2997 Housing is more resistant to wear. This change was never effective in the factory.

Adaptable To: The 224-2997 Housing is adaptable to all machines. The 224-2997 Housing will directly replace the 174-8797 Housing. The 224-2997 Housing will replace the 135-3222 Housing but two new 174-9593 Seal Rings are also required. Refer to Table 1.

Table 1

Old Part	Replacement Part
135-3222 Housing	224-2997 Housing Two 174-9593 Seal Rings
174-8797 Housing	224-2997 Housing

The 174-9593 Seal Ring is recommended for best component life.

Optional seal based off of field is 6T-0248 Seal Ring. This seal can be cut to 0.4 mm (0.01575 inch) gap to replace 174-9593 Seal Ring. This seal 6T-0248 Seal Ring will have reduced life compared to 174-9593 Seal Ring