10R80

Symptoms:

• Harsh shifts
• High line pressure

Cause:
Bore and/or piston wear in the LPC signal damper can prevent proper main line pressure control and cause excessively high line pressure.

Correction:
Sonnax drop-in LPC signal damper piston kit corrects this circuit pressure variation by replacing the worn OE damper without the need of reaming the valve body.

The LPC signal damper used in listed Ford and GM transmissions dampens any fluid pressure spikes in the LP signal (EPC) circuit from reaching the main pressure regulator valve. This prevents any significant and unintended pressure variations from affecting the main pressure throughout the circuit, and helps to provide smooth operation of the valve.

When the bore or piston wears, effective dampening of LPC signal pressure is not maintained and can leak to exhaust. This can result in harsh shifts and excessive line pressure.

This Sonnax LPC signal damper piston kit allows long-lasting and quick repair of the lower valve body casting without reaming. The O-ring provides a positive seal against critical pressure loss even in worn bores.

• Hardcoat anodized aluminum piston combats premature wear
• Annular groove added to the piston reduces wear rate
• Highly wear-resistant sleeve to prevent future wear
• O-Ring provides positive seal to prevent critical pressure leakage in already worn bores
• Mating spring re-establishes OE dampening action
• Drop-in Zip Valve™ parts install quickly and easily

Contains:

• Piston
• Sleeve
• Spring
• O-Rings (2) 1 Extra

129784K Instruction Sheet