![]() This allows the PCM to know the speed of the input shaft after the torque converter which is used in combination with crankshaft speed to detect the amount of slipping going on in the torque converter. The PCM was given a more powerful microprocessor and Ford added a turbine speed sensor to the transmission. Newer transmissions that are referred to as 4R70E or 4R75E have modifications that compliment Fords switching to throttle by wire. While not used on all 2003 model year vehicles, the 4R75W/E transmissions eventually replaced the 4R70W/E. These improvements allowed the 4R75W to handle more power while being more efficient and economical. In 2003 Ford revised the 4R70W transmission with a stronger ring gear that had 24 lugs, as opposed to 6, for the output shaft sensor (OSS) to read off of, a new torque converter, a revised front pump assembly, and a vehicle speed sensor (VSS) that complements the OSS to improve shift quality and efficiency. 4R70W indicates 4 gears, Rear wheel drive and Wider gear ratio compared to the AODE. The "70" may also refer to the transmission's torque capacity after torque converter multiplication which occurs at low rpm's when the torque converter is more "elastic". In fact a Ford document stated that the 2003 "Expedition's 4R70W transmission is rated to handle up to 506 pound-feet of torque, which provides a large performance cushion beyond the peak torque rating of Expedition's largest available engine." It is more plausible that the number indicates the torque handling capability in N-m, as 506 lb-ft converts to 686 N-m which could be rounded to 700 N-m. 700 lb-ft of torque), there is no reliable source indicating this. While there is some speculation that the 70 can be multiplied by 10 to indicate the pound-feet of torque this transmission is capable of handling, including torque converter multiplication, (i.e. In 1998, due to durability concerns, the intermediate one-way roller clutch was replaced with a mechanical diode providing extra holding capacity and longer service. On vehicles powered by the 5.4L V8, a stronger gearset is used than in normal duty 4R70Ws and Torque Converter stall speeds is also slightly lower because of the 5.4L’s increased low end torque opposed to the 4.6L. Although this may sound bad, fuel economy is slightly increased and downshifting is slightly decreased for less wear. Unlike the AOD-E, Reverse, 1st, and 2nd gear ratios in the 4R70-W are numerically higher, giving the transmission a better mechanical advantage and in turn, better take-off acceleration, better passing acceleration, slightly lower fuel consumption, and designed for better gearset strength The 4th gear ratio in the 4R70-W is up 0.70:1 from 0.67:1. 1992 and up Ford F-Series trucks and E-Series vansĪ revised version of the AOD-E Transmission was released in 1993 with the Lincoln Mark VIII.While the AOD and AOD-E are similar to each other (oil pans, casings, bell-housing, and internals), they are not interchangeable with each other because the AOD-E's shift points are controlled electronically from a combination of solenoids and the Powertrain Control Module (PCM) while the AOD's shift points are hydraulically controlled by a throttle valve rod. It was mainly intended for the new Modular V8 at first, but it was also adapted to the old AOD bell-housing for vehicles still powered by pushrod engines. The AOD was redesigned with electronic controls in 1992, becoming the AOD-E. Initially called XT-LOD (Extension Lock-Up Overdrive) its name was changed when revisited in 1974 to FIOD (Ford Integrated Overdrive) and then to its final name in 1979, the Ford AOD transmission. #Rebuilt ford aod transmission for sale full sizeThe transmission was introduced when Ford started to downsize its full size line in 1979. The project was shelved with a design that lacked a dampener in the torque converter but after the project was revisited a dampener ultimately made its way into the final design. ![]() The XT-LOD was initially abandoned in 1966 but design began again in 1974 as a result of rising gas prices. The transmission featured a split-torque application for third gear as well as a lockup in the torque converter. Because it was based on the "X" transmissions, its gear ratios from 1-3 were the same with the fourth being 0.67:1. Where many transmissions had a fourth gear added on as an afterthought, Ford's new transmission was designed with a fourth gear integrated into the gearset. The new transmission was built around the Ravigneaux planetary gearset of the "X" transmissions. In 1962 Ford began working on a new type of automatic transmission that would emphasize fuel economy and driveability. ![]()
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