4R70W Input Drum 1998, remanufactured and ready to install. Fits the 4R70W. Ships fast from the USA.
Your 1998 Ford backs up fine but will not pull in Drive, or it slips in the first three gears and the pan is full of burnt friction material. That pattern points straight at the forward clutch and the drum that carries it. This remanufactured 4R70W input drum is listed for 1998 F-150, Expedition, Crown Victoria, Grand Marquis, Town Car, Mustang and Navigator models with the 4R70W.
In the 4R70W the input drum is the forward clutch drum. It is splined to the input shaft, so it turns at turbine speed whenever the engine runs in gear. When forward clutch oil arrives from the pump through the stator support, its piston clamps the forward pack and drives the forward sun gear. That clutch is applied in first, second and third, so it takes every launch and most of the city driving. Sonnax calls forward drum breakage a chronic problem across the AOD, AODE and 4R70W, and lists no Forward, slipping gears, a broken drum and ratio codes as the results.
Soft forward engagement can also come from low line pressure or an EPC problem rather than broken hardware. Read the codes and check line pressure before you pull the transmission. Sonnax links low base line pressure to delayed Forward engagement and forward clutch failure on this family. On a 1998 also inspect the internal harness and the case connector. ATRA notes that 1998 is the first year of the black connector with the separate hard plastic harness, and that solenoids do not interchange with the 1993-1997 white-connector style. A damaged 1998-2008 internal wiring harness can cause erratic shifts and codes that look like slip. The Crown Victoria shift problems guide and the Explorer shift problems guide cover the electrical checks.
A 1998 unit uses the early forward drum. ATRA says pre-2004 drums have a single clutch apply hole and 2004-on drums have three spaced 120 degrees apart. It calls that change cosmetic, but later units also added a turbine speed sensor that reads the forward drum. Your 1998 has none of that, so match this drum to the one you removed. Compare the spline count, the sealing ring lands on the hub and the overall height. If you have a 1992 or early-production unit instead, see the 1992 4R70W input drum. Send us your year and VIN if your build date is unclear. All 4R70W parts are in the 4R70W collection.
| Fits | 4R70W 1998 |
| Part type | Input Drum |
| Condition | Remanufactured |
| Brand | OEM |
| Ships | From the USA |
| Warranty | 1-year |
Doing this repair right usually means replacing these at the same time. Same transmission, ships together.
Yes. On the 4R70W the input drum is the forward clutch drum. It is splined to the input shaft and applies the forward clutch in first through third.
ATRA says the move from one apply hole to three in 2004 is cosmetic for clutch apply. Later units also use a turbine speed sensor that reads the forward drum, so match your drum to your year and ask us before mixing generations.
Check the fluid level and condition, read the codes and test line pressure. If the pressure is good and the fluid shows burnt friction material, the forward pack and drum are the likely failure.
Replace the forward frictions and steels, the piston seals, the drum sealing rings and the filter. Check the thrust bearings and washers, and the forward sun gear and sun shell for cracks.
Use MERCON V. Ford's 2003 Crown Victoria owner guide lists about 13.9 quarts dry for the 4R70W, but capacity varies with cooler size, so fill to the dipstick hot.
