These can be mixed with thinner steels used in forward drum when setting clearance. The center support houses the intermediate apply piston, supports the direct drum. Extra fluid capacity lowers fluid temperatures. Step 4: Remove Parking Pawl Remove the parking pawl spring. As far as the automatic transmission is concerned, these efforts save great expense. Planetary gears and their thrust washers should be very carefully inspected during any transmission rebuild. So they have the option to perform many of the repairs themselves.
It is hooked to an engine manifold vacuum source to provide a reference signal to the transmission. You must plug the exhaust hole in the valve body also designated. Use care not to damage the bore around the seal. Some areas are cast iron, such as the center support for the transmission. Materials and Size The Turbo 400 is primarily constructed of cast aluminum, with the bell housing being integrated into the transmission and also made of cast aluminum. This washer must survive a tremendous amount of load and its failure will often damage the rear of the case.
The majority of internal components are interchangeable. This is a special hollow bolt; oil must flow through it to the intermediate clutch. You will remove the 2-3 accumulator piston, discard the spring. Avoid the temptation to spin the planetary pinions with a highpressure air gun. After working with the Power Automedia staff for some time on a freelance basis, Andrew joined the team in 2010. Pay attention to the orientation.
To help soften the apply force, an accumulator may be used. The stator assembly is splined directly to the stationary input splines on the front of the transmission. The servo has a return spring and retainer to quickly disengage the band when the hydraulic pressure is removed. Some transmissions also use a vacuum modulator, which is mounted to the transmission case. It uses dog-bone-shaped internal components instead of rollers. Not always necessary but it helps.
Remove Front Band and Low Band Apply Servos Step 1: Remove Front Band Apply Servo Lift the front band apply servo from the case. When dual feeding the directs as done in this build , this sealing ring is not necessary. Next are the forward, direct, and intermediate clutch packs — a combination of red racing forward and direct clutch packs and High Energy frictions intermediate clutch packs. You can also consult factory tech publications for the maximum allowable sideplay, and then measure and replace them as needed. Use a stock bushing with red loctite and staked in place. Next, you will finish assembling the rear gear train portion for installation into the case. Amateurs and professionals alike will appreciate the advice and guidance offered on every page.
I do this with a set screw. These drums are becoming difficult to obtain in good used condition. A backing plate is used in a clutch drum, behind the last friction plate. There is a snap ring that goes in the case above the pressure plate pictured. This allows you to custom-stack the clutch pack in the drum and establish the correct endplay. Step 3: Remove Outer Shaft Remove the outer shaft that splines into the sun gear. This allows the oil to flow easier, quicker to the direct drum.
If required you install the fretting snap ring into the case. Although not mandatory for all builds, doing so produces a unit that has firmer shifting, reduced gear noise, and ultimately lasts longer once placed into service. It is relatively inexpensive and can be used without pan removal with the transmission in the car. Be careful- the thin metal can cut the teflon rings and fingers. There were several different styles used. It helps to heat the rings in hot water before installing so that they will stretch easier. Before we get into the build, you may be wondering why the Turbo 400 has become a go-to automatic transmission for so many race teams, from fast bracket racers all the way up to 4,000 horsepower Pro Modifieds.
A stock snap ring can also be tack welded to the retainer. It is best to leave this assembly intact so none of the parts get lost or rearranged during cleaning. The sealing ring is left off, the ring land has been machined off. The waved plate may be used between the apply piston and a flat steel plate, or may be used directly against a friction plate. If you acquire a 4L80E direct drum be sure to have the correct race, too.