Case IH 2496 (517967.07) - DEC – Transmission Control Unit (TCU): Transm in N + Park Clutch B slipping

The transmission control system has detected unexpected slippage in the "B" clutch pack while the tractor's transmission is placed in Neutral and Park.

• VESTRUM CVX
• Case IH Vestrum CVX / CVXDrive
• Vestrum 100 CVX
• Case IH Puma CVXDrive
• Puma 130
• Puma 180
• Puma 185-240
• Case IH Optum CVXDrive
• Case IH Magnum CVT / Powershift
• Magnum 210
• Magnum 315
• Magnum 370
• CVT4100

1. 1

   Filter & Manifold Inspection: Check the transmission filter housing and manifold. Look for failure or cracking at the union with the filter cartridge, leading to pressure loss and clutch slippage.

2. 2

   Fluid & Debris Check: Drain a small amount of transmission oil and cut open the transmission filter. Look for fine silver filings or metal shavings indicating severe mechanical wear on the synchros (such as Synchro 2) or the clutch discs.

3. 3

   Transmission Calibration: Attempt to run a transmission calibration via the tractor's display. Monitor the Clutch B calibration values. If the calibration fails (e.g., logging codes like U27 or U28 for Clutch B calibration being too high/low), it confirms internal leakage or mechanical failure.

4. 4

   Pressure Test: Perform a hydraulic pressure test on the Clutch B circuit to verify if the piston seals are holding pressure.

1. 1

   Prep for Split

   Drain the transmission fluid and remove the transmission filters.

2. 2

   Access the Transmission

   Depending on the model, remove the cab and pull the hydrostatic unit off to access the transmission housing.

3. 3

   Inspect Synchronizers & Clutches

   Remove the reverse gear cover and inspect the synchronizers (specifically check Synchro 2 for broken teeth or wear).

4. 4

   Service Clutch B

   Extract the Clutch B assembly. Inspect the clutch discs for discoloration (burning) and wear.

5. 5

   Replace Seals/Housing

   Replace the Clutch B piston seals, rings, and friction discs. If the clutch housing itself is scored or damaged, replace the entire Clutch B housing.

6. 6

   Reassembly

   Reassemble the transmission, mate the tractor halves, and install new transmission filters. Refill with the OEM-specified hydraulic/transmission fluid.

7. 7

   Recalibrate

   Turn on the tractor and use the diagnostic display to perform a full transmission calibration. You must calibrate all clutches (A, B, C, D, E, F1, F2, F3, F4, and R) and synchronizers so the TCU can learn the new engagement points.