Clamps the 1-2-3-4 and 3-5-Reverse drum so you can lift it out of a GM 6L80E case and set it back on the shaft without it slipping.
Anyone who has torn down a 6L80E knows the moment: the pump is off, and the 1-2-3-4/3-5-Reverse drum is sitting deep in the case with nothing to grab. This is a clamp-style removal and installation tool equivalent to GM special tool T-47781AC. It grips that drum so you can lift it straight out and set it straight back in on the 6L50E, 6L80E and 6L90E family, 2006 and up, used behind Silverado, Sierra, Tahoe, Yukon, Suburban, Escalade, Camaro, CTS, Colorado and Canyon applications.
The 1-2-3-4 and 3-5-Reverse clutches share one housing at the front of the gear train, right behind the pump. It is tall, heavy once loaded with plates, and its outer shell is smooth enough that fingers slip off it. The tool is a locking clamp with jaws shaped to the drum and an upright handle near the centerline. Close the jaws on the drum, lock them, and the weight hangs evenly under the handle. That matters more on the way back in than on the way out: the drum has to drop over the shaft and index its clutches onto the hubs below, and a drum that goes in tilted can roll a sealing ring or never seat.
If your 6L80 has no reverse, a flare on the 2-3 shift or slip in fifth, the 1-2-3-4/3-5-R housing is high on the list, along with the 3-5-R regulator valve in the valve body. Our 3-5-R clutch failure guide explains how to tell the valve body from the drum, and the 6L80 common problems guide covers the rest. Once the drum is out, test it on a 6L80 drum leak tester before you decide to reuse it.
The tool is listed for the GM 6L50E, 6L80E and 6L90E, 2006 and up, and it is made for the 1-2-3-4/3-5-Reverse drum. It is not meant for the 4-5-6 housing at the rear of the case. Drum dimensions can differ between the light and heavy-duty members of the family, so check that the jaws sit squarely on your drum before lifting. If you are not sure which unit you have, send us the year and VIN. The rest of our six-speed tooling and parts are in the 6L80 collection.
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Doing this repair right usually means replacing these at the same time. Same transmission, ships together.
The 1-2-3-4/3-5-Reverse clutch drum at the front of GM 6L50E, 6L80E and 6L90E transmissions. It is not meant for the 4-5-6 housing at the rear.
It is an aftermarket tool built as the equivalent of GM special tool T-47781AC, with a stainless steel clamp body and a locking switch.
You can pull the drum by hand, but it is heavy and hard to grip, and dropping it or installing it crooked damages the piston bore and sealing rings. The tool makes it a clean one-person job.
It is a bench tool used once the pump is off. On a 6L80 that normally means the transmission is out of the vehicle and on a bench or fixture.
A drum leak tester, a seal ring expander, new sealing rings and pistons, and DEXRON VI for assembly lube.
