Sonnax GM 6T50 (Gen. 1) Transmission

Remanufactured Valve Body

6T40 (Gen. 1), 6T45 (Gen. 1), 6T50 (Gen. 1), 6T30 (Gen. 1) Remanufactured Valve Body GM6T40-1

Internal

3-5-R Drum Saver Kit 144555K

Helps cure:

Code P0776
Flare shifts
Harsh Reverse
No Reverse
2-3 Harsh
No 3rd
4-5 Harsh
No 5th

Bearing Kit SBK-G40

Does not fit Gen. 3 units.

Helps cure:

Bearing noise
Bearing failure

Pressure Switch Rebuild Kit 144510-09K

Helps cure:

Pressure switch codes
Pressure control out-of-range codes
Failsafe mode
Slips, flares & bind-ups
Harsh shifts
Shift codes

Pump

Oversized Pressure Regulator Valve Kit 144510-01K

Helps cure:

Erratic line pressure
Burnt clutches
Poor shift quality
Low converter & lube flow
Overheating
TCC apply & release concerns

Tooling:

F-144510-TLC
VB-FIX

Oversized TCC Control Valve Kit 144510-05K

Helps cure:

Excess TCC slip
Low cooler flow
Overheating
Low converter & lube flow
TCC apply & release concerns
TCC codes
TCC lining failure

Tooling:

F-144510-TL5C
VB-FIX

Valve Body (View Valve Body Layout Diagram)

Actuator Feed Limit Valve Kit 144740-39K

Helps cure:

No 4th
No 5th
No 6th
Low clutch oil pressure
Harsh shifts
Flare shifts

Checkball 10000-08

Material: Imidized Plastic
Dia.: 0.250"

Helps cure:

Lost or damaged component

Compensator Feed Regulator Valve Kit 104740-09K

Helps cure:

Harsh shifts
Downshift clunk
3-4 Bump
Bump shifts
Flare shifts
Bind-up
Burnt clutches
Overheated fluid

O-Ringed End Plug Kit 144740-02K

Helps cure:

Pressure loss
Burnt clutches
Shift concerns
TCC apply concerns

Oversized Actuator Feed Limit Valve 144740-01

Helps cure:

No 4th
No 5th
No 6th
Low clutch oil pressure
Harsh shifts
Flare shifts

Tooling:

144740-TL

Oversized Clutch Boost Valve 144740-22

Helps cure:

Slip codes
Delayed engagement
1-2-3-4 Clutch burned
Shift quality is not load sensitive
Harsh shifts
Slide shifts
Slips & flares

Tooling:

F-144740-TL22
VB-FIX

Oversized TCC Regulator Valve Kit 144740-16K

Helps cure:

Code P0741, P0742
No lockup
TCC slip
Loss of fuel economy
Low TCC apply pressure
Overheated fluid & TCC lining
Harsh TCC apply

Tooling:

F-144740-TL16
VB-FIX

TCC Regulator Valve Kit 144740-38K

Helps cure:

Code P0741, P0742
No lockup
TCC slip
Loss of fuel economy
Low TCC apply pressure
Overheated fluid & TCC lining
Harsh TCC apply

Vacuum Test Plate Kit 144740-VTP

Tooling:

VACTEST-01K

Vacuum Test Plate Kit Seal 144740-VTP-S

Tooling:

144740-VTP
VACTEST-01K

Zip Kit® 6T40-ZIP

Helps cure:

Burnt clutches
Line pressure instability
Loss of fuel economy
No line rise
Pressure loss
Pressure switch codes
Shift concerns
TCC apply & release concerns
TCC codes

Other

Tool Kit F-144740-TL22

Tooling:

VB-FIX

Tool Kit F-144740-TL16

Tooling:

VB-FIX

Tool Kit F-144510-TL5C

Tooling:

VB-FIX

Tool Kit F-144510-TLC

Tooling:

VB-FIX

Tool Kit 144740-TL

Tech Resources

January 25, 2023

Uncovering the Root Cause of Pressure & Complaints – The Critical Role of Solenoid Modulator & AFL Valves

Maura Stafford

December 29, 2022

Zip Kit FAQ: What's Up with Plugging Separator Plate Ports?

July 20, 2020

Conquering the GM Compensator Clip Conundrum

Andrew Jessiman

July 01, 2020

Always Identify These Valve Bodies BEFORE You Start a Transmission Rebuild

Andrew Jessiman

September 19, 2019

GM 6T40 & 6T70 Drum Saver Kits: Unbeatable Protection Against 3-5-R Failures & Comebacks

September 10, 2019

Protect Against 6T40 & 6T70 3-5-R Failures & Salvage Damaged Drums with Sonnax Drum Saver Kits

March 23, 2015

Sonnax Webinar: GM Gen. 1 6T40, 6T45, 6T50 Concerns & Repair Techniques

December 23, 2014

GM 6T30/40/45/50 (Gen. 1) Valve Body Layout

October 31, 2014

GM 6T30, 6T40, 6T45, 6T50 (Gen. 1) Vacuum Test Guide

October 30, 2014

Transmission Report: Money in the Bank - The GM/Ford Joint Venture

October 27, 2014

Under Pressure: Shift Quality & Pressure Switches in TEHCM Applications

September 18, 2014