5R55W Clutch Drum 2002, remanufactured and ready to install. Fits the 5R55W. Ships fast from the USA.
Explorer and Mountaineer owners usually end up shopping for a 5R55W overdrive drum after the same story: the truck started flaring on the 1-2 shift, then slipped out of 5th on the highway, and when the transmission came apart the overdrive band was burnt and the drum it rides on was glazed or heat-checked. This is a remanufactured overdrive drum assembly for the 2002-and-later 5R55W and 5R55S geartrain, supplied with the overdrive sun gear and thrust washer. Each one is torn down, cleaned, washed, inspected for cracks, and has its band surface resurfaced so a fresh band can grip it properly. There is one detail every W owner needs to check before ordering, and it is covered under Fitment below.
In the 5R55W the overdrive band is the holding member for two forward gears. It clamps this drum in 2nd along with the forward clutch, and again in 5th along with the forward and direct clutches. The coast clutch pack sits inside the same drum and is used in reverse. ATSG notes that the coast clutch drum also passes lube oil from the front pump to the overdrive planetary, so the drum is part of the oiling path as well as a friction surface. When the drum surface is damaged, a new band cannot hold it, and the truck slips in exactly those two gears.
The W is known for wearing the servo pin bores in the case. Sonnax describes apply oil leaking past the worn pin and release oil cross-leaking into the apply circuits, which lets the band slip and burn. If you replace the drum and band without fixing the bore, the new parts get cooked the same way. Confirm the slip is in 2nd and 5th only, check fluid level and condition, and read our 5R55W Explorer slipping guide and the 5R55W P0730 incorrect gear ratio guide, which explains how a band slip and a wrong-ratio planetary both set the same code.
Sonnax places the W in the Explorer and Mountaineer for 2002 and 2003 before the S took over, and identifies the W by a 24-tooth overdrive sun gear and the S by a 38-tooth one. That tooth count is what gives the W its 2.41 second gear and 0.75 overdrive, against 2.29 and 0.71 for the S. The sun gear supplied with this drum is the 38-tooth version, built for the 2002-and-up W and S units that use it. Before you order, pull your old sun gear and count it. If yours has 24 teeth, installing a 38-tooth gear changes your 2nd and 5th ratios, and the computer may flag a ratio fault, so match your original or send us your year and VIN first. The 5R55S vs 5R55W differences guide lays out the ratio split, and every 5R55 part we stock is on the 5R55 parts page.
| Fits | 5R55W 2002 |
| Part type | Clutch 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.
Sonnax places the 5R55W in the Explorer and Mountaineer for 2002 and 2003, with the 5R55S taking over after that. Send us your VIN if you are not sure which one your truck has.
It comes with the 38-tooth overdrive sun gear. Count the teeth on your original sun gear before ordering, because Sonnax identifies the W by a 24-tooth gear and the tooth count sets your 2nd and 5th ratios.
Replace the overdrive band, the coast clutch seals and the rebuild-kit seals and gaskets, and repair the overdrive servo pin bore in the case if it is worn. A worn bore is the most common reason the band burnt in the first place.
It can. P0730 means the computer saw the wrong ratio between input and output speed. A slipping overdrive band on a damaged drum, or a sun gear with the wrong tooth count, will both produce that.
Mercon V. The 5R55W has no dipstick, so it is filled and checked through the plug in the case with the transmission at operating temperature.
