Symptoms:

  • TCC codes
  • TCC apply & release concerns
  • Converter shudder
  • Burnt converter

Cause:

TCC regulator valve bore wear allows loss of crucial apply pressure.

Correction:

恢复液压控制和更新苑沟纹e by reconditioning the bore and installing Sonnax oversized TCC regulator valve kit.

4L80-E,4L85-E

Oversized TCC Regulator Valve Kit
Part No.34994-18K


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

GM vehicles equipped with 4L80-E and 4L85-E transmissions may exhibit problems such as TCC shudder, burnt converter linings, TCC apply and release concerns and related codes. These issues can often be caused by critical pressure loss due to excess wear in the TCC regulator bore. Reconditioning the bore and installing Sonnax oversized TCC regulator valve kit 34994-18K shores up the hydraulic integrity of the TCC control circuit to return robust TCC operation.

  • Hardcoat anodized aluminum valve combats premature wear
  • Lengthened critical spool for added stability and wear prevention
  • Annular grooves help center valve in bore to reduce future side-load wear
  • Added chamfer to improve apply characteristics and prevent shudder
  • Two springsincluded in kit; one for OE lockup feel, the other provides firmer-than-OE
  • Valve
  • Sleeve
  • Springs (2)
  • Retaining Pin

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.

GM 4L80-E, 4L85-E, 400 Valve Body Layout

GM 4L80-E, 4L85-E, 400 Valve Body Layout
  • 4L80-E, 4L85-E Oversized TCC Regulator Valve Kit 34994-18K
  • 4L80-E, 4L85-E Oversized TCC Regulator Valve Kit 34994-18K
  • 4L80-E, 4L85-E Oversized TCC Regulator Valve Kit 34994-18K details

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.

4L80-E, 4L85-E Oversized TCC Regulator Valve Kit Vacuum Test Locations