5R55S Master Rebuild Kit 2008, new and ready to install. Fits the 5R55S. Ships fast from the USA.
A 2008 or later 5R55S that slips coming out of a stop, flares into the next gear or has gone dark and burnt is usually ready for new clutches and seals. This kit is aimed at that job. It is catalogued as a Raybestos banner kit, part number W16004GAP, for 2008-up 5R55S and 5R55W units, and it pairs a complete overhaul kit with a bonded piston and twelve high-energy friction plates: five double-sided direct clutch frictions (48 teeth, R560107), five forward clutch frictions (89 teeth, R560100) and two overrun clutch frictions (16 teeth, R560020). In this period the S sat behind the 4.0L V6 in the Mustang and in the Explorer and Mountaineer.
The 5R55S uses three multi-disc clutches (forward, direct and overrun) and three bands. The overhaul kit side brings the gaskets, seals, O-rings, sealing rings, lip seals and rubber components, so every circuit that feeds a clutch or servo gets a fresh seal. The bonded piston replaces a molded-seal piston whose rubber hardens and leaks apply oil with age. The friction set covers the three clutch packs that most often come out glazed on a high-mileage S.
Be clear on what is not included. There are no steel plates, no bands and no filter in this box. That makes it a good fit for a rebuild where the steels come out flat and unblued and the bands still have lining. When the steels are heat-discolored or the bands are burnt, plan to buy those separately or step up to a full master kit such as the 5R55S master rebuild kit for 2000-2010.
Pull the pan before you commit. Sonnax notes that worn valve body bores and VFS modulator valves on the W/S can cut clutch and servo pressure enough to set gear ratio codes and cause slippage, and that the solenoid pack is often blamed for problems that start elsewhere. If the fluid is clean and red, work the hydraulic side first using our 5R55 harsh or delayed shift walkthrough. If the bands and servos are the issue, read the servo pin bore wear guide, because new frictions do nothing for a worn case bore. A furry magnet and burnt fluid point to a teardown and this kit.
This listing covers 2008 5R55S transmissions, and the kit is catalogued for 2008-up S and W units. Inside the kit, only the friction plates and the bonded piston need careful matching. Count the teeth on your old frictions (48 on the direct clutch, 89 on the forward clutch, 16 on the overrun) and compare them to the plates listed above before the old ones go in the scrap bin. If your unit is a 2002-2007 build, the earlier version is a better match. Not sure which you have? Send us the year and VIN before you order. You can see every part we carry for this family on the 5R55 parts page, and our 5R55S identification guide walks through telling an S from a W or N.
| Fits | 5R55S 2008 |
| Part type | Master Rebuild Kit |
| 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.
No. It contains the overhaul kit with a bonded piston plus 12 friction plates. Steels, bands and the filter are sold separately. If your steels are blued or your bands are burnt, buy those as well or use a full master kit.
It is catalogued for 2008-up 5R55S and 5R55W transmissions. Before you install, compare tooth counts on your old frictions with the kit plates: 48 teeth direct, 89 teeth forward, 16 teeth overrun. Send us your year and VIN if you want us to check.
Loss of engine braking often points to the overrun clutch or its circuit, and this kit includes two new overrun frictions. Check for valve body leaks first, because a leaking circuit will burn up new frictions too.
Mercon V. Sonnax notes that early Mercon V factory fills caused problems in these units, so flush the cooler and lines completely so old fluid does not contaminate the rebuild.
Yes. Units built after 2002 use adaptive shift strategy, so clear the stored adaptive values and let the computer relearn during a road test. Expect shift feel to settle over the first drives.
