• TCC codes
  • TCC slip
  • No lockup
  • TCC cycling
  • Overheated fluid
  • Low cooler & lube pressure
  • Loss of fuel economy


Excess wear of TCC apply boost valve and sleeve allows critical pressure loss, resulting in TCC apply and release concerns.


Recover hydraulic control and renew TCC performance by installing Sonnax drop-in TCC apply boost valve kit.


TCC Apply Boost Valve Kit
Part No. 126740-03K

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

Ford 6R140 transmissions often display TCC-related concerns due to deterioration of the TCC apply boost valve and/or sleeve. As wear progresses, pressure loss causes various symptoms to arise such as TCC slip, no lockup, insufficient cooler or lube pressure, overheated fluid, suffering fuel economy and/or TCC codes. Restore normal TCC operation and revive cooler/lube flow by installing Sonnax TCC apply boost valve kit 126740-03K.

  • No special tools or reaming required
  • Hardcoat anodized aluminum valve combats premature wear
  • Sleeve manufactured from highly wear-resistant aluminum
  • Drop-in Zip Valve™ parts install quickly and easily
Learn More About Zip Valve™ Drop-In Repairs
  • Boost Valve
  • Sleeve

Sonnax valve body layouts provide a detailed overview of individual units making it quick and easy to determine what’s available for the specific valve body you’re working on. See all Sonnax valve body layouts.

Ford 6R140 Valve Body Layout

Ford 6R140 Valve Body Layout
  • 6R140 TCC Apply Boost Valve Kit 126740-03K
  • 6R140 TCC Apply Boost Valve Kit 126740-03K

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.

6R140 TCC Apply Boost Valve Kit Vacuum Test Locations