PISTON AS 4904250 - Caterpillar

Introduction
A 9W1572 Shaft (transmission input) is now available as the parts service replacement for the 6P1543 Shaft used in the above machines.The 9W1572 Shaft is grooved, to use O-ring seals, for improved bearing retention.The former 6P1543 Shaft used dowels for bearing retention. The installation of the 9W1572 Shaft requires the use of two 6Y0296 Bearings and two 8M4390 O-ring Seals.They are not included with the 9W1572 Shaft and must be ordered separately.Refer to Machine Model and Transmission Effective Serial Numbers, in this instruction, for the serial number range of the transmissions that require the use of the new parts if being repaired or updated.Reference: Service ManualMachine Model and Transmission Effective Serial Numbers
The following list, by machine sales model, shows the effective transmission serial number range for factory installation of the 9W1572 Shaft, 8M4390 O-ring Seals and 6Y0296 Bearings.988B ... 2MA04115, 1JE00844834B ... 1KE00454Installation of the 9W1572 Shaft, 8M4390 O-ring Seals and 6Y0296 Bearings
1. Refer to the Service Manual for the transmission removal and disassembly procedures.
1. 8M4390 O-ring seals. 2. 9W1572 Shaft. 3. 6Y0296 Bearings.The illustration above shows the transmission shaft installed, the shaft MUST be removed from the transmission for this repair.
The grooved areas on the shaft and the O-ring seals MUST be lubricated immediately before the installation of the bearings.Failure to do can cause damage to the O-ring seals and/or prevent the bearings from seating properly.
2. Install, after lubrication, two 8M4390 O-ring Seals (1) in the grooved areas of 9W1572 Shaft (2).Inspect the O-ring seals to ensure they have not twisted during installation and have seated properly in the grooves. The 6Y0296 Bearings (3) may be installed with shields (4) orientated (facing) in either direction.3. Install two 6Y0296 Bearings (3).Inspect the bearings to ensure they have seated properly against the O-ring seals.4. Refer to the Service Manual to install transmission shaft and transmission.