TCC Switch Oversize Valve - ZF 8HP45/55/70 Sonnax

Innovative oversize valve (Oversize TCC Switch Valve) from renowned company Sonnaxfor the regeneration of hydraulic controllers in transmissions ZF 8HP45, 8HP55 and 8HP70. The original TCC Switch valve in the aluminium mechatronics body wears out, causing pressure leaks. This leads to problems in the operation of the converter lock-up clutch, such as jerking, vibration, overheating of the transmission and errors in the controller.

Technical specifications:

• Manufacturer: Sonnax
• Condition: New
• Transmission type: 8-speed automatic (ZF 8HP45/55/70)
• Sonnax catalogue number: 35740-05
• Attention: Requires a special tool (reamer) for assembly!

Application:

The kit allows a worn valve seat in the mechatronics body to be permanently repaired. Instead of replacing the entire, expensive unit, the worn seat is reamed out with a dedicated Sonnax tool and a new, oversized valve from the kit is installed. This restores perfect tightness and proper operation of the lock-up system.

Key benefits:

• Permanently eliminates problems with the operation of the lock-up clutch (TCC)
• Solves vibration and jerking problems at constant speed
• Prevents overheating of the gearbox and converter
• Much cheaper option than replacing the entire mechatronics

Installation instructions:

This is an operation for highly specialised workshops. It requires disassembly and dismantling of the mechatronics. The worn valve seat is reamed using a dedicated Sonnax reamer (sold separately). A new valve from the kit is then installed.

Summary:

Sonnax's TCC valve repair kit is an advanced but highly effective solution to common problems with 8HP transmissions. It is the flagship product for professionals who want to offer the highest quality remanufacturing, permanently eliminating a known factory defect.