700R4 Input Drum 1987-1992, remanufactured and ready to install. Fits the 700R4. Ships fast from the USA.
This is the reverse input drum for the last cable-controlled years of the 700R4, 1987 through 1992 (GM renamed the unit 4L60 in 1989). It is a remanufactured GM drum with new bushings installed, and it is the round feed hole version with no check ball. If your Chevy or GMC pickup, Blazer, Suburban, Camaro or Caprice from those years has no Reverse, or the 2-4 band keeps burning, and your old drum is cracked or worn, this is the like-for-like replacement.
The reverse input drum feeds apply oil to its piston through a hole between the sealing ring lands. During the 700R4 run GM changed that passage more than once, which is why drums are sold by year group. This one has the round hole and no check ball. Matching the drum your unit was built with keeps the reverse clutch apply and release where the hydraulic system expects them. Before ordering, look between the sealing ring grooves on your old drum: a round hole with no ball confirms this style.
The 2-4 band wraps the outside of this drum and holds it for 2nd and 4th gear, while the reverse input clutch inside locks it to the input in Reverse, when it turns the sun shell to drive the gear train. A drum that has lost its band surface or bushing fit hurts three gears at once.
Keep in mind the 700R4 sun shell also fails and takes Reverse with it; check it before deciding the drum is the cause. See 700R4 common problems and fixes.
Gauge line pressure first. Low pressure from the TV cable, the pump or a leaking accumulator checkball burns bands and reverse clutches regardless of drum condition. The 700R4 pump failure symptoms guide covers the pump side. Once apart, check for bushing play on the stator shaft, sealing ring groove wear and band surface damage.
Fits 1987-1992 700R4 and 4L60 transmissions built with the round feed hole, no check ball drum. That covers the cable-shift GM rear-drive cars and trucks of those years. Because the drum changed during 1987, early-1987 units may use the older style; confirm with your old drum or send us your year and VIN. For a 1992-and-later unit, see our 1992-up loaded reverse input drum, and find the rest of this family on the 700R4 transmission page.
| Fits | 700R4 1987-1992 |
| Part type | Input Drum |
| Condition | Remanufactured |
| Brand | GM |
| Ships | From the USA |
| Warranty | 1-year |
Doing this repair right usually means replacing these at the same time. Same transmission, ships together.
Look at the feed passage between the sealing ring grooves on the drum hub. This drum has a round hole and no check ball.
It is listed for 1987-1992 700R4/4L60 units. 1993-up electronic units use a later drum, so match your original part or send your VIN.
It is a remanufactured GM drum with new bushings installed, sold as a bare drum.
A new 2-4 band, reverse input frictions and steels, piston seals and stator shaft sealing rings.
Dexron-type ATF. Dexron-VI is backward compatible with the original Dexron-II spec, so it is a correct fill. Pre-soak the new frictions in the same fluid before assembly.
