Clutch Release System Wear/Damage - Endurant and PACCAR Transmissions

Updated: July 21, 2025

Issue Description:

Over repair/under repair of the Clutch Release System (and/or clutch) due to a lack of troubleshooting wear measurement criteria. For customers experiencing an illuminated transmission service lamp and Fault Code 511 (SPN 5614) FMI 7, 10, refer to TAIB-0885.

Containment/Corrective Action:

Document Clutch Release System and/or Clutch Diaphragm Spring wear troubleshooting measurement criteria and Clutch Release System damage to look for per this TAIB.

Affected Models/Population:

• Endurant HD, XD Transmissions
• PACCAR TX12, TX18 Transmissions

Field Strategy:

This document only applies if Fault Code 706 SPN 2983 FMI 17 or 18 is set Active or Inactive or you were sent here from TAIB-0885, perform the clutch release system inspection detailed in the Service Strategy section.

Service Strategy:

Reference Endurant HD Automated Transmission Service Manual TRSM0950 and XD Automated Transmission Service Manual for all service procedures.

HD Transmissions:

1. Inspect Input Shaft Pilot Bearing Wear Sleeve for excessive wear.

• If excessive wear is found, inspect the pilot bearing for wear and/or failure.
  • If pilot bearing wear and/or failure is found, replace pilot bearing per OEM guidelines.
  • If input shaft pilot bearing wear sleeve wear and/or damage is found, replace input shaft pilot bearing wear sleeve.

    Note: Pilot bearing replacement is non-warrantable. Input shaft pilot bearing wear sleeve wear and/or damage is non-warrantable.

  • Go to Step 2.
• If no excessive wear is found, go to Step 2.

XD Transmissions:

1. Inspect Input Shaft Pilot Bearing journal for excessive wear.

• If excessive wear is found, inspect the pilot bearing for wear and/or failure.
  • If pilot bearing wear and/or failure is found, replace pilot bearing per OEM guidelines.
  • If input shaft pilot bearing journal wear and/or damage is found, replace input shaft.

    Note: Pilot bearing replacement is non-warrantable. Input shaft journal wear and/or damage is non-warrantable.

  • Go to Step 2.
• If no excessive wear is found, go to Step 2.

2. Inspect Release Bearing

• HD
  • If release yoke casting has come into contact with release bearing casting, replace the release yoke, release yoke pivot pin, and the release bearing. Go to step 7.
• XD
  • If release yoke casting has come into contact with release bearing casting, replace the release yoke and the release bearing. Go to step 7.
• If the release bearing inner sleeve is cracked or broken, replace the release bearing. Go to Step 6.
• If the inner wave spring is protruding from the face of the bearing, replace the release bearing. Go to Step 6.
• If the release bearing outer baffle has rotated fully outside of the original staked position, replace the release bearing assembly. Go to Step 6.

New	Partially Rotated (Reuse)	Rotated (Replace)

3. Inspect release bearing assembly for wear and/or “divots” on wear pads from rollers. Document the wear measurements in the warranty claim notes.

• If wear is found, measure wear with a caliper.
• If wear and/or “divot” measurement exceeds 0.5 mm in depth, replace the Release Bearing assembly. Go to Step 6.
• If wear and/or “divot” measurement is less than 0.5 mm, go to Step 4.

4. Measure Release Bearing assembly for wear.

• Place release bearing assembly on the workbench with the bearing side up.
  • With a pair of vernier calipers, measure from the top of the wear crown to the roller yoke contact area (Not in the release yoke roller divot that was just measured and not in the lowest point of the bearing surface).
  • Equal pressure will need to be applied to the other side of the bearing when making this reading.

Measuring an ISO Bearing

• ISO Bearing (P/N 125969, A-10004340) Minimum Specification is 51.80 mm.
• SAE Bearing (P/N 125968, A-10004341) Minimum Specification is 44.95 mm.
• If bearing is under specification, replace release bearing assembly. Go to Step 6.
• If bearing is within specification, go to Step 5.

5. Place release bearing assembly (bearing side down). With downward pressure rotate the release bearing assembly by hand. New or low hour bearings will have a higher rolling resistance (New seals and new grease).

Rotate with pressure	Rotate checking for seal drag

• If the release bearing is hard to turn (seized or partially seized) replace the release bearing. Go to Step 6.
• If the release bearing shows no signs of seal drag, replace the release bearing. Go to Step 6.
• If the release bearing does not rotate smoothly with downward pressure, replace the release bearing. Go to Step 6.

  Note: A release bearing that does not meet the inspection criteria in the steps 2, 3, 4, and 5 is not considered to be failed but cannot be reused.

6. Inspect the release yoke, release yoke pivot pin, release yoke plastic sockets for damage.

• If the release yoke pivot pin is broken, replace the release yoke pivot pin, release yoke, and the release bearing. Go to Step 7.
• HD:
  • If release yoke casting has come into contact with release bearing casting, replace the release yoke pivot pin and the release bearing. Go to Step 7.
• XD:
  • If release yoke casting has come into contact with release bearing casting, replace the release yoke and the release bearing. Go to Step 7.
• New 125891 Release Yoke (Used on HD and XD)
• HD:
  • Inspect release yoke rollers (both sides) for lateral (Fore and Aft) movement and Up and Down Movement. If roller movement is found, replace the release yoke, release yoke pivot pin, and the release bearing. Go to Step 7.
• XD:
  • Inspect release yoke rollers (both sides) for lateral (Fore and Aft) movement and Up and Down movement. If roller movement is found, replace the release yoke and the release bearing. Go to step 7.

Fore and Aft	Up and Down

• Release Yoke and Plastic Sockets (New)
• If Release Yoke Pivot Pin and/or Release Yoke and/or plastic sockets are damaged, replace Release Yoke Assembly and Release Yoke Pivot Pin. Go to Step 7.
• If no movement is found in both rollers, the release yoke casting has not come into contact with the release bearing casting, and the plastic sockets are not damaged, reuse the release yoke. Go to Step 7.

7. Inspect the Clutch Diaphragm Spring for wear. Reference Eaton CLIB0040.

8. If no observed Clutch Release System and/or Clutch Diaphragm Spring wear is within the acceptable limits found in this Service Bulletin or Eaton Clutch Service Bulletin, continue with troubleshooting as appropriate.

HD:

Note: It is highly recommended to implement the new High Preload (HPL) LCA, new reduced weight release yoke and replace the release yoke pivot pin at the time of clutch replacement. The introduction of the HPL LCA and the reduced weight release yoke will improve the clutch release system dynamics between the release yoke, release bearing, and diaphragm spring of the clutch cover (Customer Pay if not found to be warrantable).

XD:

Note: All production transmissions were built with the new High Preload (HPL) LCA and the reduced weight release yoke. It is not recommended to replace the release yoke pivot pin unless damaged.

Note: HD and XD transmissions do not share the same release yoke pivot pin and are not to be interchanged. XD transmission release yoke pivot pin is shorter, HD transmission pivot pin is longer. Installing an HD pivot pin on an XD transmission may result in a FC 250 or a clutch that may not calibrate.

Warranty Information:

Warranty Parts (if warrantable):

Endurant HD Parts Book - TRPB0950	Endurant XD Parts Book - TRPB0960

Warranty Labor (if found warrantable) (ECWY3000):

• Diagnostics (Up to 1 Hour)
• Transmission R&R (Up to 3.4 hours)
• Release Yoke R&R (Up to 0.1 Hour)
• Release Yoke Pivot Pin R&R (Up to 0.1 Hour)
• Release Bearing R&R (Up to 0.1 hour)
• Test Drive (Up to 0.3 Hour)

The material contained in this bulletin is product improvement information. Eaton Corporation is not committed to, or liable for, canvassing existing products.

FSUD: 4226