6L80 Shift Kit, new and ready to install. Fits the 6L80. Ships fast from the USA.
If your Silverado, Sierra, Tahoe, Yukon or Escalade flares between gears with a trailer behind it, or your Camaro or Corvette shifts lazily at wide open throttle and you are worried about the clutches, this is the kit most builders reach for. It is a new TransGo 6L80-TOW&PRO Reprogramming Kit, TransGo's performance and towing calibration for 2006 and later 6L45, 6L50, 6L80 and 6L90 units. It is not the base SK6L80 kit; it is the more aggressive version built for trucks that work and cars that make power.
The 6L80 has no shift valves in the old sense. The TEHCM fires solenoids, and the valve body uses those signals to move a regulator valve for each clutch: 1-2-3-4, 3-5-R, 4-5-6, 2-6 and the low/reverse. How fast and how hard a clutch applies depends on the springs and valve geometry inside those regulator and boost circuits. TransGo says this kit reworks the 2-6, 3-5-R and 4-5-6 clutch regulator and boost valves, raises maximum line pressure, and steepens the pressure curve, with valve body and pump parts in the box. The goal is factory feel at light and medium throttle, then progressively firmer upshifts toward wide open throttle, without software tuning. Shorter overlap means less time with a clutch slipping under load, which is what cooks friction material when towing.
A shift kit is a calibration fix, not a repair for broken hardware. If you already have slip codes such as P0776 or a burnt pack, the clutches have to be replaced at the same time.
Rule out the cheap stuff first. Low or degraded Dexron VI, a stuck adapt table, or a worn actuator feed limit bore can all mimic a weak calibration. Reset transmission adapts and run a relearn; GM's own fix for some harsh 6L80 shifts is exactly that. Then compare commanded and actual line pressure with a gauge, as described in our 6L80 Silverado 1500 shift problems guide. If shifts are harsh rather than soft, read the 6L80 harsh shift causes guide before adding more pressure. A kit that firms things up will not fix a bump that comes from a sticking valve or a misbuilt clutch pack.
TransGo lists the 6L80-TOW&PRO for 2006-on 6L45, 6L50, 6L80 and 6L90 transmissions, which covers the 6L80 in GM full-size trucks and SUVs, Camaro, Corvette and Escalade. Upper and lower valve body castings changed over the years and differ by RPO, so the kit's instruction sheet covers the steps for each version. Check the RPO on your door or glovebox sticker (MYC for the 6L80) and keep your casting numbers handy. If you are unsure, send us your year and VIN before ordering. More parts for this unit are in our 6L80 parts collection.
Plan on doing this with the valve body on the bench, ideally during a rebuild. Work one area at a time, lay removed springs and valves out in order, and follow the TransGo instructions exactly, including the pump components. Replace the filter and its case seal and refill with Dexron VI through the check plug at the specified temperature. Afterward, reset adapts and let the TCM relearn before judging shift feel. If the clutches are worn, install a 6L80 master rebuild kit in the same teardown, and if your valve body bores are already worn, a replacement 6L80 valve body gives the kit a clean base to work from.
| Fits | 6L80 |
| Part type | Shift Kit |
| Condition | New |
| Brand | TransGo |
| Ships | From the USA |
| Warranty | 1-year |
Doing this repair right usually means replacing these at the same time. Same transmission, ships together.
No. This is the 6L80-TOW&PRO Reprogramming Kit. TransGo describes it as its performance and towing kit, with increased maximum line pressure and a more aggressive pressure curve than a stock-feel repair.
TransGo states it keeps factory shift feel at light to medium throttle and firms upshifts progressively toward wide open throttle. Harshness at light throttle after install usually means an adapt reset or relearn is still needed.
No. The kit is hydraulic and works without software changes. TransGo notes optional HP Tuners or EFI Live shift-time changes for owners who want even firmer hard-throttle shifts, used together with this kit.
The valve body and TEHCM come out from under the vehicle, but the kit includes pump components as well, so most installs are done during a rebuild or full valve body service on the bench.
Dexron VI, filled and checked through the check plug at operating temperature. Replace the filter and case seal while the pan is off.
