TransGo SK6R80-G2 Shift Kit for Ford 6R80 6-Speed

This is the TransGo SK6R80-G2, the second-generation version of TransGo's 6R80 valve body repair kit. It is meant for the later Ford 6R80, the one built from January 2015 on in the F-150, Expedition, Navigator and Mustang, and TransGo also lists it for the 2017-on 6R100. If your 2015-or-newer truck quivers between roughly 28 and 46 mph as if a tire were out of round, clunks as it coasts down to a light, or slurs through hot upshifts, the pressure regulator and converter clutch regulator circuits in the valve body are where TransGo aims this kit.

What the SK6R80-G2 does in a GEN2 6R80

Every clutch apply in the 6R80 starts with line pressure set by the pressure regulator (PR) valve in the main valve body. As the aluminum bore wears, that valve leaks past its lands and line pressure wanders, so shifts stretch out and the converter clutch cannot hold steady. Ford enlarged the PR valve on the GEN2 casting, which is why this kit is not interchangeable with the earlier one. The G2 kit drops in a hardened steel two-piece PR valve with a new boost valve, a white PR spring and a four-groove end cap, plus a steel TCC regulator valve with its own small calibration spring. The longer lands on both valves ride on sections of the bore that never wore, so the circuits seal again without reaming. Six solenoid damper inserts and four bore plug wire retainers round out the box.

Symptoms the kit targets

• A shudder or quiver at about 28 to 46 mph while the converter clutch is applying
• Converter clutch slip and erratic line pressure
• Soft or long shifts, worst once the fluid is hot
• A clunk on coast downshifts
• Gear ratio codes P0729 and P0731 through P0734
• Shift solenoid performance codes P0781 through P0784 and P0829

How to confirm the valve body is the cause

On a 2015-2017 F-150, check open recalls before anything else. Ford's 2026 recall 26S28 covers about 1.39 million of these trucks built from March 2014 to August 2017 for a degrading lead frame that can send a false range signal and cause an unexpected downshift, and that is a wiring fix, not a valve body fix. Our 6R80 F-150 shift problems guide walks through those codes. With electrical faults ruled out and the fluid level confirmed hot, a shudder that only appears while the converter clutch is applied, and ratio codes without circuit codes, point at the PR and TCC regulator valves. For harsh or bound-up shifts that are really a solenoid or adaptive issue, see our harsh shift causes guide.

Fitment

TransGo's instructions say Ford's parts book shows every vehicle built after December 2014 with a GEN2 valve body, but they warn that some 2014 and early 2015 trucks, and some new replacement GEN1 valve bodies, have the extra filter hole and look like a GEN2 while still using the small PR valve. So measure the original PR valve before you open the kit: .514 in is GEN2 and this kit fits; .495 in is GEN1, and you need our 2006-14 GEN1 6R80 shift kit instead. The G2 kit fits GEN2 valve bodies with or without Start Stop, but only with stock factory bore sizes. Not sure what you have? Send us your year and VIN, or browse the 6R80 parts collection.

Install notes

• The valve body comes out through the pan, so this can be done in the truck. Mark every solenoid's position before removal; the brown and black snout variable force solenoids carry a calibration number from 2 to 5 and must go back where they came from.
• Install the new boost valve and spring, PR valve and cap, and confirm the PR valve moves freely. Replace the TCC regulator valve and spring with the steel valve and small white spring.
• Reinstall all eight plastic check balls in their original spots (Start Stop units also have an 8 mm steel ball and spring), replace any flattened damper, and check every wire retainer.
• Refill with Mercon LV, set the level hot, and allow for the adaptive relearn.
• TransGo notes that valve bodies past about 140,000 miles also wear the solenoid and lube regulator bores and need fresh solenoids. If the casting is past saving, a 2015-2018 6R80 valve body is the cleaner fix, and if the clutches are burnt, install the kit during a rebuild with a 2015 6R80 overhaul kit.

Will the SK6R80-G2 fit my 2013 F-150?

Almost certainly not. A 2013 truck has a GEN1 valve body with the smaller .495 in pressure regulator valve, which takes TransGo's SK 6R80-A GEN1 kit. The G2 kit is for GEN2 valve bodies with the .514 in PR valve, generally builds from January 2015 on.

Does it work on trucks with Start Stop?

Yes. TransGo lists the G2 kit for GEN2 6R80 valve bodies with or without Start Stop. Start Stop units use a two-neck filter and have an extra 8 mm steel check ball and spring that must go back in its original spot.

Will it cure my 6R80 torque converter shudder?

It replaces the TCC regulator valve that TransGo identifies as the cause of the 28-46 mph quiver, and installers report a fresh fluid refill with the kit usually clears it. If the shudder has gone on for many months, the converter clutch itself may be damaged and need replacing.

Do I need to ream the valve body?

Not for this kit. The PR and TCC regulator valves are drop-in with longer lands. Reaming only comes into play for the solenoid and lube regulator bores on high-mileage valve bodies, which is a separate TransGo repair.

What fluid goes back in after the install?

Ford specifies Mercon LV for the 6R80. Set the level with the fluid at operating temperature using a scan tool, and expect shift feel to settle over a few days as the adaptive tables relearn.

• 6R80 F150 Shift Problems: Diagnosis and Fix
• 6R80 Harsh Shift Causes and Fix
• 6R80 Shift Solenoid Symptoms and Replacement
• 6R80 Common Problems and Fixes