4L80E Shift Kit, new and ready to install. Fits the 4L80E. Ships fast from the USA.
This is the Superior K4L80-E Shift Correction Package for the GM 4L80E, the valve body kit to look at when a Chevrolet or GMC 2500 or 3500, Suburban 2500, Express or Savana van, or Hummer H1 shifts differently every time, shudders on converter lockup, or has a history of pressure problems. It is new, made in the USA, and comes with regular duty and heavy duty calibrations in the same box, so one kit covers a daily driver and a truck that tows.
The 4L80E depends on a steady, predictable line pressure. The pressure regulator valve in the pump sets the base pressure, the EPC solenoid raises it with throttle, and a separate actuator feed circuit supplies the shift and lockup solenoids through a small screen. When the regulator train wears, pressure can rise unevenly or climb out of control, and the computer can no longer make the same shift twice. Superior's answer is to supply a complete pressure regulator valve train with the kit rather than reusing worn stock parts. Superior says that new train is a failsafe that stops runaway high pressure, the condition that cracks 4L80E cases, before it starts.
The rest of the kit revises valve body circuits to firm up and even out the shifts. You choose the regular or heavy duty set of changes when you install it, based on how the vehicle is used.
Lockup shudder and erratic shifts have other causes too. A worn converter clutch, a failing TCC solenoid, old fluid or a bad EPC solenoid can all feel the same from the driver's seat. The U.S. Army 4L80E troubleshooting guide separates firm, harsh and flare complaints and lists resistance values for each solenoid, which is the right first test. Our EPC solenoid symptoms guide shows how to check pressure control, and the 4L80E won't shift into overdrive guide covers missing shifts and lockup faults. If line pressure is unstable on a gauge with good solenoids, the valve body kit is the fix.
The K4L80-E is cataloged for 1991-2010 GM vehicles with the 4L80E. That covers Chevrolet and GMC 2500 and 3500 pickups, Suburban 2500, Express and Savana vans, Hummer H1 and medium-duty applications. A 4L80E pan has 17 bolts, which is a quick way to tell it from a 4L60E. The valve body and solenoids changed during production, so read the instruction sheet section for your year before modifying anything. If you are not sure which unit you have, send us your year and VIN, or look through the 4L80E parts collection for matching parts.
| Fits | 4L80E |
| Part type | Shift Kit |
| Condition | New |
| Brand | Superior |
| Ships | From the USA |
| Warranty | 1-year |
Doing this repair right usually means replacing these at the same time. Same transmission, ships together.
It is cataloged for 1991-2010 GM vehicles with the 4L80E. Confirm you have a 4L80E by the 17-bolt pan, or send us your VIN.
The kit includes parts and instructions for both. Use the regular setting for a daily driver and the heavy duty setting for a vehicle that tows or hauls a lot. Pick one and follow only that set of steps.
It fixes shudder caused by unstable pressure. If the converter clutch is worn or the TCC solenoid has failed, those parts also need to be replaced.
Worn regulator parts let line pressure rise unevenly or run away. Superior includes a complete new valve train so the regulator is fresh and limits pressure, which protects the case.
DEXRON-VI, GM's current fluid for 4L80E trucks. Check the level at operating temperature and do not overfill.
