• Reverse slip
  • Gear ratio codes
  • 3rd Slip
  • 4th Slip
  • Direct clutch burned
  • No Reverse


Excess wear in Reverse checkball sleeve prevents proper application of direct clutches.


Restore hydraulic control and prevent premature wear by installing Sonnax drop-in reverse checkball sleeve.

4L80-E, 4L85-E

Reverse Checkball Sleeve
Part No. 34200-38

Fits units '95-later.

Package Quantity: 4

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

Vehicles with '95-later GM 4L80-E and 4L85-E transmissions commonly exhibit wear in the Reverse checkball sleeve located in the 3-4 shift valve bore. This issue is caused by normal movement of the checkball within the sleeve over time. As wear progresses, sealing function of checkball becomes compromised and results in loss of apply pressure to direct clutches. Consequences of this pressure loss are slipping or no 3rd, 4th, and Reverse gears, burnt direct clutches, and ratio codes.

Installing Sonnax Reverse checkball sleeve 34200-38 restores the hydraulic integrity of this circuit to reestablish normal shift operation and performance.

  • Sleeve is manufactured from highly wear-resistant aluminum for maximum life
  • Drop-in Zip Valve parts install quickly and easily
Learn More About Zip Valve™ Drop-In Repairs

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, TH400 Valve Body Layout

GM 4L80-E, 4L85-E, TH400 Valve Body Layout
  • 4L80-E, 4L85-E Reverse Checkball Sleeve 34200-38
  • 4L80-E, 4L85-E Reverse Checkball Sleeve 34200-38

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 Reverse Checkball Sleeve Vacuum Test Locations