4R100 Input Drum, new and ready to install. Fits the 4R100. Ships fast from the USA.
A 4R100 that has thrown metal, lost a gear, or chewed through its center support usually takes more than a box of clutches to fix. When the input drum itself is worn, cracked or blued from heat, reusing it means the new frictions start life on a damaged part. This listing is a new 4R100 input drum, not a used or remanufactured core, for the Ford automatic used from 1998 to 2004 in F-250 through F-550 Super Duty trucks, the Excursion and E-Series vans with the 7.3L Power Stroke, 5.4L and 6.8L V10.
The 4R100 is Ford's 1998 update of the E4OD, which itself was a C6 main case and gear train with an electronic overdrive section added on the front. Engine torque comes through the converter and overdrive section into the main box, and the input drum is one of the rotating members that carries that torque into the clutch packs and planetary set behind it. Like every drum in this unit it has splines that drive plates or a mating shell, and it runs against bushings and thrust surfaces on its neighbors. Because it turns at input speed under full load, wear at its journals and contact points shows up early on hard-working trucks.
Sonnax specifically lists input drum wear at the center support as a known problem in the E4OD and 4R100, along with excess wear of the center support and case lugs at their contact points, and it sells a center support ring to correct it. If the support has moved or worn, it can let the input drum run off center, which wears the drum, its bushing and the clutch it feeds. That is why a high-mileage tow rig often needs this drum replaced, not just inspected.
Electrical and pressure faults come first. Scan the truck, check the solenoid pack resistances, and confirm line pressure; our shift solenoid symptoms guide covers the tests for this family, and the E4OD and 4R100 common problems guide lists the mechanical failures by symptom. If those checks pass and the transmission still slips or makes metal, it needs to come apart. On the bench, look at the drum splines and tabs for wear or cracks, measure the bushing, and inspect the center support and case lugs for the wear pattern Sonnax describes. A drum with damaged splines or a worn journal cannot be repaired by resealing it.
The listing names this part as a 4R100 input drum and does not give a year range or Ford part number. The 4R100 was built for 1998 through 2004, but the name input drum is used loosely in this family, so compare the new part with the one you are removing: outer diameter, height, spline count, tab or lug pattern and the bore. The photo shows a stamped steel drum with internal splines and slotted tabs around the open end. If you are unsure, send us your year, VIN and a photo of the old part before ordering. Everything for this transmission is on the E4OD and 4R100 parts page.
Clean and inspect the parts that mate with the new drum, including the shell or hub it drives, the thrust washers and bearings on either side, and the center support. A new drum running against a worn support or bushing will wear the same way again. Replace the clutches it serves along with the seals and sealing rings, set clutch clearances to spec, and air-check every circuit before the pan goes on. The 4R100 overhaul kit provides the gaskets and seals for this job, and the 4R100 sprag clutch for 1999-2004 is worth replacing if the unit made metal. Flush the cooler, refill with MERCON V, and check the level hot in Park.
| Fits | 4R100 |
| Part type | Input Drum |
| Condition | New |
| 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.
Ford used the 4R100 from 1998 to 2004 in F-250 through F-550 Super Duty trucks, the Excursion and E-Series vans with the 7.3L diesel, 5.4L and 6.8L V10. Most 6.0L diesel trucks use a different five-speed.
It is listed as new. That avoids the hidden spline and journal wear that can come with a used drum from a high-mileage unit.
Do not assume it will. Ford changed several front-end parts between the E4OD and the 4R100. Compare the new drum with your old one, or send us your VIN and a photo.
The center support and case lugs for wear, the thrust washers and bearings around the drum, and the clutch pack it serves. Sonnax lists input drum wear at the center support as a known issue.
MERCON V automatic transmission fluid, checked hot in Park with the engine running.
