6T40 Shift Kit 2013

If your 2013-2017 Chevrolet Cruze, Sonic, Trax or Buick Encore flares between gears, feels lazy on the 1-2 or 2-3, or keeps setting pressure control and torque converter clutch codes after the fluid was already changed, the wear is often inside the valve body, not the clutches. This is a new TransGo SK 6T40-G2 SHIFT KIT valve body repair kit for the second-generation 6T40. It replaces the three valves TransGo identifies as the usual wear points in this valve body with hardened steel parts made in the USA.

What this shift kit does in a Gen 2 6T40

The 6T40 is fully electronic: the TEHCM commands pressure control solenoids, and the solenoids set clutch apply pressure. That only works if the oil feeding them is steady. The actuator feed limit (AFL) valve caps solenoid feed pressure, the pressure regulator valve sets line pressure and responds to the boost signal, and the TCC regulator valve controls converter clutch apply. When their aluminum bores wear, oil leaks past the valves, solenoid feed drifts, line pressure boost comes late, and the clutches slip on every shift. The SK 6T40-G2 includes:

• An oversized hardened steel AFL valve, installed after the bore is reamed with TransGo tool kit AFL-G2-TK, sold separately
• A drop-in hardened steel pressure regulator valve and spring with longer lands
• A drop-in hardened steel TCC regulator valve with a scarf cut sealing ring, spring and O-ring that seals in the original worn bore

Symptoms it is built to correct

• Soft shifts or flare-up between gears, worst when the fluid is hot
• Burned friction plates found during a rebuild, or a rebuilt unit that slips again
• Erratic or hunting torque converter clutch apply, with P0741
• Slow pressure boost when you step into the throttle
• Pressure control solenoid and gear ratio codes such as P0751, P0752, P0776, P0777, P0796, P0797, P2714, P2715, P2723 and P2724

How to confirm the valve body is the cause

Those codes can also come from a failed solenoid, a TEHCM fault, a cracked 3-5-R wave plate or simply a wrong fluid level, so test before you buy. Check the level hot at the level set plug, read the codes and freeze frame, and compare commanded and actual pressures with a scan tool. Our 6T40 shift solenoid symptoms guide covers resistance checks and how to tell a solenoid from a feed pressure problem, and the 6T40 valve body symptoms guide explains what each worn bore does to the drive.

Fitment

TransGo catalogs this kit for Gen 2 6T30, 6T40 and 6T45 transmissions from 2013 to 2017 built without pressure switches. GM began the Gen 2 changeover for 2012 with some exceptions, so year alone does not settle it. Read the eighth digit of the TEHCM part number to confirm generation, and check for pressure switches on the control solenoid body. A first-generation unit needs the 6T40 shift kit for 2007-2012 instead. If you are unsure, send us your year and VIN. The same TransGo kit is also listed for the smaller 6T30 Gen 2 transmission.

Install notes

• Order the AFL-G2-TK reaming tool kit before you start; the oversized AFL valve cannot go in without it.
• Follow the TransGo instructions in order and keep removed valves and springs laid out as they came out.
• Do not shuffle the solenoids; each sits in a factory-calibrated position on the TEHCM.
• Install the kit during a rebuild or valve body service. If the clutches are burned, replace them, and if the bores are too far gone, a replacement 6T40 valve body for 2010-2017 may be the better path.
• Refill with Dexron VI, set the level hot, and run the Service Fast Learn so the TCM relearns clutch fill with the new pressures.

Which TransGo kit is this?

It is the TransGo SK 6T40-G2 SHIFT KIT valve body repair kit for Gen 2 6T30, 6T40 and 6T45 transmissions, 2013-2017, without pressure switches.

Is the reaming tool included?

No. The oversized AFL valve requires TransGo tool kit AFL-G2-TK, which is sold separately. The pressure regulator and TCC regulator valves drop in without reaming.

Will it fit my 2012 Cruze?

Only if the transmission is a Gen 2 unit without pressure switches. Some 2012 units are Gen 2 and some are not, so check the TEHCM generation digit or send us your VIN.

Will this kit make my 6T40 shift harshly?

It restores the pressure control that worn bores lost, so shifts should firm up and stop flaring. Run the fast learn after installation so the TCM adjusts its adapts.

Can it clear codes like P0776 or P2723?

TransGo lists those codes among the conditions it corrects when bore wear is the cause. A broken 3-5-R wave plate or a failed solenoid can set the same codes, so diagnose first.

• 6T40 Shift Solenoid Symptoms and Replacement
• 6T40 Valve Body Symptoms: What Wears, What It Does to the Drive, and How to Test It
• 6T40 Harsh Shift Causes and Fix
• 6T40 Common Problems and Fixes