RE5R05A Input Drum 2003, used and ready to install. Fits the RE5R05A. Ships fast from the USA.
When a 2003 Nissan or Infiniti five-speed automatic comes apart with a twisted input spline, sealing ring grooves worn into steps, or gear teeth chipped inside the front drum, the fix is a hard part, not another clutch kit. This is a used, original-equipment RE5R05A input drum for 2003. As the photo shows, it is the input shaft and the drum it carries as one piece: a long splined shaft with its sealing rings in place, rising out of a wide drum whose inside wall is cut with helical gear teeth. It comes with a 1-year warranty and costs a fraction of a complete core.
Every bit of engine torque that leaves the converter goes through this assembly first. The converter turbine drives the splined end of the shaft, and the shaft turns the drum. The helical teeth on the inside of the drum make it an internal gear for the planetary set it surrounds, so the drum feeds power straight into the geartrain while the clutches and brakes around it decide which ratio comes out the back. The shaft does a second job as a fluid passage. Look at the photo and you will see several ring grooves along its length; oil for the rotating clutches travels down drillings in the shaft, and the sealing rings in those grooves keep it from leaking off between the spinning shaft and the parts around it. That is why the condition of the ring grooves matters as much as the gear teeth.
Rule out the simple things first: fluid level, fluid condition and codes, as laid out in our RE5R05A service and diagnosis guide. If the fluid is pink and milky, a failed radiator cooler has let coolant in; Sonnax reports that about half of RE5R05A cores show it, and you will be replacing much more than this part. With the unit on the bench, inspect the input spline, the gear teeth and each ring groove on the shaft. The ATRA case in Gears Magazine is the one to know: a Frontier with a repeat harsh 1-2 shift had no burnt clutches at all, yet it needed 70 psi of air to apply the direct clutch because a steel ring land had worn to 0.018 inch of clearance instead of the expected 0.005 inch. The wear was a small step in the groove that is hard to see by eye, so the writer suggested photographing the lands and enlarging the pictures. Grooves worn like that on your shaft are a good reason to replace it.
This listing is for the 2003 RE5R05A. The unit first appeared in the 2002 Infiniti Q45, so a 2003 assembly comes from the early, car-based production years, before the 2005-up Frontier, Xterra, Pathfinder, Titan and Armada trucks. Input shafts can differ in length, spline count and drum design between engines and years, so measure your old shaft and count its splines against the photo before installing, or send us the year and VIN and we will check it. The full RE5R05A lineup is on our RE5R05A parts page.
| Fits | RE5R05A 2003 |
| Part type | Input Drum |
| Condition | Used |
| 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.
The photo shows the input shaft and the drum as one assembly. The splined shaft and its sealing rings rise out of a drum with internal helical gear teeth. You get the assembly shown.
Do not assume it will. This assembly is listed for the 2003 RE5R05A, which comes from the early car years. Shaft length, spline count and drum design can change between applications. Measure and compare with your old part, or send us your year and VIN.
One documented cause is worn ring grooves (lands) that leak apply oil, so the direct clutch applies slowly. In the Gears Magazine case, a land measured 0.018 inch of ring clearance against an expected 0.005 inch. Check every ring groove on the shaft and support.
New sealing rings, thrust washers and bearings, plus a master rebuild kit for the seals, gaskets and frictions. Inspect the planetary carrier that meshes with the drum teeth while you are in there.
Genuine Nissan Matic-S ATF, with Matic J as Nissan's listed alternative. If the old fluid had coolant in it, replace or bypass the radiator cooler first.
