TH400 rebuild tech
(→Rebuilding the T-400) |
m (→Rear planetary setup) |
||
| Line 89: | Line 89: | ||
[[file:Reaction_tube.jpg]] | [[file:Reaction_tube.jpg]] | ||
| + | |||
| + | |||
| + | Also of note, | ||
| + | Pictured is a late style reaction carrier and an early style. I believe the early style was only used on 1964-1966 models. Notice the actual sprag type element used on the early style on the right. I prefer these type for high-HP transbrake builds although not mandatory. | ||
| + | |||
| + | |||
| + | |||
| + | My "compressor/sizer" for the sealing rings. | ||
| + | |||
| + | Next, you will finish assembling the rear portion for installation into the case. | ||
| + | Install the center support into the reaction carrier. | ||
| + | |||
| + | Complete. | ||
| + | |||
| + | You will install the rear thrust bearing into the case or the stock selective in the case with the stock thrust on the rear planet (using assembly gel, petroleum jelly, or grease to hold in place). | ||
| + | You will also install the low/reverse (rear) band. | ||
| + | If required you install the fretting snap ring into the case. ATSG covers when this is necessary, most later model (71?-up trans have this). | ||
| + | |||
| + | |||
| + | I install the part of the rear servo to help hold the band in place. Not always necessary but it helps. | ||
| + | |||
| + | |||
| + | Now you will need to lift the rear assembly and install. This rear assembly is relatively heavy. It requires you to lift by the center shaft, you cannot lift it by the center support as it will slide out of the reaction carrier. | ||
| + | I use a paper towel to pad it slightly, and grip the shaft between my middle and index finger. I lift it using one hand under the output carrier until I'm ready to set it into the case. Then all the weight is on your fingers for a few seconds. If you have a helper they may be able to hold the output shaft once it passes through the rear case hole and hole in the bench. | ||
| + | The center support must line up with the holes in the case, you can see two angle cut tangs on the center support in about the 8 and 10 o'clock position as pictured, these can be used to line it up properly. | ||
| + | |||
| + | Once the assembly is seated in the case, be sure the feed holes in the valve body area line up properly, the rear band apply is in the correct location. | ||
| + | Install the center support bolt finger tight, then install the beveled case ring with the gap at the 9 o'clock position. | ||
| + | Then using a screwdriver through one of the feed holes in the VB area, force the center support in a counterclockwise direction and tighten the center support bolt. | ||
| + | |||
| + | This picture shows a common roller clutch style drum and a roller clutch on the left, most TH400's will use this style drum, early units, pre-71 will have the smooth inner race style drum on the right. 4L80-E's also use the "early" style drum and an actual sprag. The stock 16 element sprag is in the center, with the 34 element on the right. | ||
| + | |||
| + | |||
| + | |||
| + | This is a pic of an upgrade for high rpm applications, it is a spiro lock type retainer instead of a regular snap ring. The regular snap rings will release due to centrifugal forces at high rpms. | ||
| + | |||
| + | This part is a stock 4L80 part available at a GM dealership. | ||
| + | Edit/Delete Message | ||
===Center support assembly=== | ===Center support assembly=== | ||
Your Privacy Choices