Manual Transmission: Notes
WARNING: This page is about a different car, the 2004 Ford Pickup, 2004 Ford F550 Super Duty, 2004 Ford F450 Super Duty, and 2004 Ford Cab & Chassis. However, it is still accessible from the selected car via links, so may be relevant.
The S6-650 and the M6HD transmissions are six-speed synchronized units. The ZF six speed has the following features:
- An integral clutch housing
- An aluminum main case, extension housing, and intermediate housing
- The mainshaft has two tapered roller bearings. Mainshaft end play is controlled by a selective shim located under the bearing cup
- The countershaft has two tapered roller bearings. The countershaft end play is controlled by a selective shim located under the bearing cup
- The countershaft is serviced as an assembly
- Synchronized in all gears
- All gears are helical
- All gears, including reverse, turn on needle roller bearings
- Single-piece shift forks with moly coated pads
- Internal oil pump, driven by the countershaft, to supply transmission fluid to an external cooler
- Provisions for mounting a power take-off unit
- A reverse idler gear that does not need to be removed during disassembly
- The mainshaft and countershaft are assembled under preload. If the ZF transmission is disassembled, a preload measurement must be taken
The S6-650 and the M6HD have six forward speeds that feature a LOW gear for take-off under heavy loads and a OVERDRIVE gear for highway driving conditions. The gear ratios are as follows:
- Low 5.79:1
- First 3.30:1
- Second 2.10:1
- Third 1.31:1
- Fourth 1.00:1
- Overdrive 0.72:1
- Reverse 5.23:1