4L70E Input Drum 1987-2014, new and ready to install. Fits the 4L70E. Ships fast from the USA.
If your Silverado, Sierra, Tahoe, Yukon, Avalanche or Trailblazer SS keeps burning 2-4 bands, flares on the 1-2 shift, or has gone soft in Reverse, the drum the band wraps around is often the real problem. This is a new genuine GM reverse input clutch housing, part number 24245624, the drum most rebuilders call the input drum or reverse drum in the 4L70E and the rest of the 4L60 family. It is a bare housing, not a loaded assembly, and it is the current GM number that replaced the older 8681295, 8642905 and 24241494 drums.
The housing rides on the pump hub at the front of the gear train and has two working faces. The outside diameter is the friction surface for the 2-4 band. When the band applies, it stops this drum and the reaction sun shell its tabs drive, and that is how the 4L70E gets 2nd and 4th gear. The inside holds the reverse input clutch pack and its piston. In Reverse that clutch locks the drum to the input and drives the same sun shell the other way. So a single part touches 2nd, 4th and Reverse, and a heavy 4L70E truck that tows leans on it hard.
Sonnax lists burned 2-4 bands, delayed Reverse and no Reverse among the documented 4L70E complaints, but several of those also come from valve body and servo problems, so the drum is not automatically guilty.
Rule out pressure first. Low line pressure from a worn pressure control solenoid or a sticking valve will slip a perfect band, and our 4L70E pressure control solenoid guide shows how to check it. If Reverse is the complaint, the 4L70E common problems guide covers the low-reverse and valve faults that look the same from the driver seat. With the unit apart, run a straightedge across the band surface, feel for ridges, and air-check the reverse input piston for a firm apply.
GM catalogs 24245624 for its rear-drive four-speed automatics from the 700R4 years through 2014, and this listing is offered for 1987-2014, which takes in every 4L70E built. Because this one housing serves 4L60, 4L60E, 4L65E and 4L70E units, it is also a common pick for a mixed-parts rebuild. Bushing and minor detail revisions happened over that span, so compare the part number on your old drum, or send us your year and VIN before you order. If what you actually need is the input housing that carries the forward and 3-4 clutches, that is a different part: see the loaded 2005-up 4L70E input drum. Everything else for this unit is in our 4L70E parts collection.
If the whole unit is open, a 2004-2010 master rebuild kit covers the seals, gaskets and frictions in one box.
| Fits | 4L70E 1987-2014 |
| Part type | Input Drum |
| Condition | New |
| Brand | GM |
| Reference | 24245624 |
| Ships | From the USA |
| Warranty | 1-year |
Doing this repair right usually means replacing these at the same time. Same transmission, ships together.
GM names it the reverse input clutch housing. Many shops and parts catalogs call it the input drum or reverse drum. It is the drum the 2-4 band wraps around, not the housing with the forward and 3-4 clutches.
No. It is a new bare housing. Plan on new reverse input clutches, piston seals and a new 2-4 band, or use the parts from a rebuild kit.
GM uses 24245624 across the 4L60, 4L60E, 4L65E and 4L70E family, and it supersedes 8681295, 8642905 and 24241494. Match the number on your old drum or send us your year and VIN to be sure.
A worn or out-of-round drum surface is one cause. Low line pressure and servo problems are the others, so check pressure and the servo before you install new parts.
GM specifies Dexron VI for 4L70E applications. Soak new frictions and the band in fresh Dexron VI before assembly.
