Transmission Components On Certain 446 Backhoe Loaders Need To Be Updated Caterpillar

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 must be administered as soon as possible. When reporting the repair, use "PI3524" as the Part Number, "7751" as the Group Number, "56" as the Warranty Claim Description Code and "T" as the SIMS Description Code. Exception: If the repair is done after failure, use "PI3524" as the Part Number, "7751" as the Group Number, "96" as the Warranty Claim Description Code, and "Z" as the SIMS Description Code.

Completion Date

Termination Date

Problem

Improved parts need to be added to transmission control, oil lines, and oil pump. Modifications need to be made to the torque converter and oil fill gauge on certain 446 Backhoe Loaders.

Affected Product
Model & Identification Number

446 (6XF1-207, 6XF209-462

Parts Needed

Dealers will need to order parts for this Program.

4- 3D2824 Seal

6- 3E6267 Cartridge

1- 8E8763 Gear Assembly

1- 5P6911 Hose-Bulk (79 cm long)

1- 5P6718 Seal

1- 9M4972 Clip

2- 6V4366 Seal

2- 6V8260 Seal

1- 6V8637 Connector

6- 6V9746 Seal

1- 9X2352 Hose-Bulk (85 cm long)

2 9X3760 Coupling

2 9X3791 Coupling

Action Required

Parts Stock

Rework all 7T9407 Selector & Pressure Control Groups by replacing all 7X6282 Cartridges with 3E6267 Cartridges and return to parts stock. If any screens are missing, disassemble the control group to retrieve the lost screens.

Rework all 9W2740 Solenoid Valve Groups by replacing the cartridge with a 3E6267 cartridge and return to parts stock.

Rework ail 6Y6282 Pump Groups by replacing 6Y6714 Gear Assembly with 8ES763 Gear Assembly and return to parts stock.

Remove all 6Y6714 Gear Assemblies and 6Y1246 Tube Assemblies in parts stock.

Affected Product

See the attached procedure.

Owner Notification

U.S. and Canadian owners will receive the attached owner Notification.

Service Claim Allowances

NOTE: This is a 10-hour job.

Parts Disposition

U.S. and Canadian Dealers

Return all 6Y1247 Tube Assemblies (protect from damage or contamination) and 7X6282 Cartridges removed from parts stock and a copy of the claim to:

Handle other parts in accordance with your Warranty Bulletin on warranty parts handling.

All Other Dealers

Handle the parts in accordance with your Warranty Bulletin on warranty parts handling.

NOTE: MAKE EVERY EFFORT TO COMPLETE THIS PROGRAM AS SOON AS POSSIBLE.

Attach.

(1-Owner Notification)

(2-Rework Procedure)

Copy Of Owner Notification For U.S. And Canadian Owners

Rework Procedure

1. Remove transmission, following instructions in the Service Manual.

2. Remove torque converter from transmission.

3. Secure converter to a mill table as shown in Illustration 1. Make sure to position the tangs so that the shaded portion of the tangs can be removed by moving the mill as shown in Illustration 2.

Illustration 1.

4. Using a dial indicator on the outside bearing diameter, center the mill over the converter.

5. Move over distance (A) to mill the first tang face. Distance (A) will vary depending upon the size of the cutter, but be sure to mill enough off to clean up the entire face of the tang. The mill cutter should be set deep enough to cover the entire length of the tang. Protect the torque converter bore to keep all dirt and chips out. If any chips get into the bore, the converter must be scrapped and a new converter used.

Illustration 2. Converter Tang Update

6. Return to the center and then move over distance (B), which must be equal to distance (A) in Step 5. Mill the second face to match the first machined face.

NOTE: It is critical,that the opposite tang faces be in line through the center of the bore. The finished tang width is not critical, but should be as large as possible.

7. Unclamp the converter and position to mill the other two tang faces, or rotate on a rotary table approximately 35°.

8. Repeat Steps 4 through 6 to complete the second set of tang faces.

9. Remove transmission oil pump from transmission.

10. Disassemble oil pump and replace 6Y6714 Gear Assembly with 8E8763 Gear Assembly.

11. Assemble oil pump and install in transmission using two 6V4366 Seal, two 6V8260 Seal, and one 5P6718 Seal. Install torque converter in transmission.

12. Remove oil lines tube assemblies from transmission and filter. Make two hose assemblies using 9M4972 Clip, four 6V9746 Seal, and four 3D2824 Seal. Reuse 6V9007 Elbows at hose connection to transmission and 6V8637 Connector at filter inlet. Use one new 6V8637 Connector at filter outlet connection. See Illustration 3.

Illustration 3. Oil Lines Update

14. At the hydraulic control group replace the cartridge in all six solenoid groups. Remove the coil nut and slide the coil off the cartridge.

15. Using a 1-" thin wall deep well socket, remove the cartridge assemblies. Care must be taken to keep dirt out of the control. Make note by the solenoid number if there is a screen in the end of each cartridge.

Illustration 4. Transmission Control

16. If the screen is missing from solenoid number 1, 2, or 6, the control must be removed from the transmission and disassembled to retrieve the screen (an 8 mm diameter pancake type screen). Remove 17 hex head bolts and remove the control from the transmission. Separate the manifold from the valve group by removing three socket head bolts. The missing screens may be located in the control, in the manifold, or laying on the top deck of the transmission. Expend all reasonable effort to locate and remove all of the missing screens.

Illustration 5.

17. If the screens are on solenoids 1, 2, and 6 but missing from solenoids numbered 3, 4, and/or 5, it is not necessary to remove the control to retrieve the screens.

18. Assemble components and install transmission in machine. Use two 6V9746 Seals to assemble oil lines from transmission cooler to transmission.

19. Remove the transmission oil level gauge from the fill tube. Add a vent to the top of the gauge as shown in Illustration 6. Cut the rubber seal only, not the steel cab when adding the vent.