4L80E 4L85E Transmission TCC Regulator Valve Kit Sonnax 34994-01K This TCC regulator apply valve kit with a hard-anodized aluminum valve with PTFE seal prevents valve bore related problems. Sonnax offers a replacement TCC regulator apply valve kit 34994-01K that will prevent valve-bore related problems. Hard-anodized aluminum valve incorporates a PTFE seal at the main wear area of the bore to prevent oil loss. The valve spool land at the spring end has been lengthened to provide greater bore-to-valve surface contact, thus further preventing leakage. The valve spool has annular grooves to help center the valve in the bore.