As a result, Ford engineers added a spring to give the 3-4 shift valve a helping hand. Begin with a plate and alternately stack clutch discs and plates. Anytime the converter is multiplying torque, which happens under all acceleration, however light, fluid temperature increases because there is an increase in pressure and resistance to fluid flow. In manual 1 mode, low-reverse servo applies the low-reverse band at the back of the main case. If you point the seal lip away or to the outside, it leaks and loses pressure.
Sometimes it does not come out with the filter. All of these items are checked by dropping the valve body and visually inspecting them. Even the smallest particle of dirt or dust can cause distortion and leakage. First Gear in Manual 1 As in drive range, the forward clutch is applied, tying the input shaft to the forward sun gear. Step 13: Install Bolts and Torque to Spec Torque Fasteners Install the bolts with lubricated threads and torque the bolts to 15 to 19 ft-lbs in a crisscross fashion for uniform tightening.
The harness protects the wiring. I did some research on some of the more popular forums that discuss the 4R70W , , and found some people mentioning that they were able to use the cooler lines to perform a fluid exchange. Pressure causes the lip to seal. The plates should have a good crosshatch pattern. Step 12: Assemble Pump Halves Make sure all holes line up, then mate and secure the pump halves. Thanks to Rick who provided this tip after installing this pan on his 2002 F—150 with the 4R70W transmission. Unsourced material may be challenged and.
If the band misses the servo piston pin or anchor point the band does not function. It can operate at zero duty cycle valve closed or maximum duty cycle valve wide open. Direct Clutch Assembly Step 1: Install Direct Clutch Piston Seals When removing the old direct clutch piston seals, observe the seal installation and lip direction. Step 9: Install Direct Clutch Snap Ring With all clutches and steels installed and clearances checked. Chrysler added overdrive units to existing 3-speed automatics: the 904 and 727. Work the sun gear drive shell back and forth to seat. The tailshaft housing is also known as the extension housing.
There are two bands, two one-way clutches, and four friction clutches used to lock and drive the gearsets. Valve body installation mandates the utmost care with proper bolt placement. 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. Allow the excess tubing to hang down to the ground and cut the tubing where it meets the ground. Unfortunately, this turn of events occurred at the 2-3 upshift, which caused clutch and band slippage, along with destructive heat.
Step 8: Replace Shaft Seal and Install Manual Shift Linkage Always replace the manual shift shaft seal while you have the transmission apart. What makes this different from most automatic overdrives is where lockup takes place: inside the overdrive unit instead of the torque converter via an inner input shaft. Install the intermediate clutch servo piston in the front pump. It is all performed by feel. Control Improvements The throttle valve does the work of two components: the vacuum modulator and the kickdown linkage. This is a very tight configuration for an open-end wrench. Step 8: Choose Pan and Gasket The transmission pan goes on next, using the best gasket available.
One planetary member is driven while the other is held. This is an adjustment that must be precise or it can cause serious transmission damage. Step 5: Install Overdrive Servo Piston Lube the overdrive band servo piston before installation. Not good, but no harm done. Closely inspect all hard parts for scoring and cracking. I think I had around. During final assembly, always check endplay.
Intermediate Clutch Installation Step 1: Install Intermediate Clutches Place the intermediate clutch discs and steel plates in the case. I'm pretty sure people would be willing to pay extra for a value added feature like that. The throttle valve is linear and spring loaded. Both have seals that should be replaced during a rebuild. Seal protectors are available from most automatic transmission parts supply houses.
Ford also recommends performing your troubleshooting step-by-step so you never miss a critical step that could lead you right to the problem. Internal Final Assembly Step 1: Install Output Shaft and Ring Gear You install the output shaft, ring gear, and direct clutch assembly as a unit. Then re-torque them for a final check. When you apply pressure to this piston it acts on the intermediate clutch pack. A trusted machine shop can cut a new groove for the snap ring that allows you to add clutch friction and steel plates.