• Delayed Forward
  • Coastdown Neutral
  • Flare shifts
  • K1 Clutch burned


The K1 clutch control valve provides source pressure for control of clutch apply and release. Responding to TCU and the linear solenoid, the K1 control valve will establish control timing of apply and release relative to engine torque. Bore wear can cause either an overlap, bind-up or premature exhausting of clutch pressure, resulting in a flare shift.


The Sonnax wear-resistant sleeve and valve correct circuit pressure loss and restore control timing of the K1 clutch control valve.


Required tool kit F-25741-TL25 is no longer in production. Check with your distributor for availability.

09D, TR-60SN

K1 Clutch Control Valve Kit
Part No. 25741-25K

You need this if... View Instructions Find a Distributor

In Aisin AW TR-60SN and VW/Audi 09D units, bore wear at the K1 clutch control results in delayed engagement into Drive, flare on 4-5 upshift and harsh 5-4 coast downshift. This bore wear will cause a clutch overlap condition (bind-up) or premature exhaust of clutch pressure (flare). Installing Sonnax K1 clutch control valve kit 25741-25K will correct source pressure and clutch control timing.

  • Hardcoat anodized aluminum valve combats premature wear
  • The tuned spring is included to maintain OE operating pressures with the new valve
  • Sleeve
  • Valve
  • Spring
  • 09D, TR-60SN K1 Clutch Control Valve Kit 25741-25K
  • 09D, TR-60SN K1 Clutch Control Valve Kit 25741-25K

You need this if...

Vacuum testing at the port(s) indicated fails to hold the recommended minimum in-Hg, or if wear is visually detected.

09D, TR-60SN K1 Clutch Control Valve Kit Vacuum Test Locations