Signal dampers are used in GM 9T45/50/60/65 transmissions to dampen or smooth out the signal fluid pressure applied from each control solenoid before the fluid flows to their respective valve. These components help provide a smooth operation of the transmission by removing the pressure spikes. When the bore and/or pistons wear out, they cannot effectively dampen the variation in pressure. This can result in poor shifting control (soft shifts), loss of oil pressure, no converter apply, hydraulic-related converter warning codes and ultimately a burnt clutch.

Replacing these worn out dampers can require replacing the valve channel casting or the entire control valve body. Other products require reaming out the bore and installing an oversized piston. Sonnax drop-in signal damper piston kit 184740-01K allows long-lasting and quick repair of the valve channel 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 to reduce wear rate
• Highly wear-resistant sleeve prevents 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