4R/5R55E Engine Stall on Engagement After Rebuild

一个当地的一般维修车库带来了一个5R55E.transmission并转换到传输商店进行重建。传输从1997年的4.0升福特探险家中出来，里程表上有216,456英里。该商店有正确的重建传输和有货的转换器，所以换回零件是将设备返回车库所必需的。

After what seemed to be a routine R&R, the technician started to fill the transmission with ATF. Everything seemed to perform normally when the transmission was in the park or neutral range, but the engine would stall abruptly when the transmission was placed into any drive range. The transmission shop was called and the decision made to have the vehicle towed back to the transmission shop for a closer look.

When the vehicle arrived, the tow truck driver said that he was able to drive the vehicle onto his rollback. Despite this information, all of the normal external performance checks were completed before an attempt was made to drive the vehicle. All of the tests, including a cooler flow check, proved to be within the proper parameters. The only thing out of the ordinary was a P0743 code for an electrical signature fault discovered during the scan check. The technician reasoned that the TCC was being applied because of a faulty or incorrect solenoid. When the vehicle was road tested, performance was satisfactory. The only hint of a malfunction was a sensation of what was described as a slight dragging of the torque converter clutch.

The decision was made to inspect and/or replace the TCC solenoid, so they dropped the transmission pan. When the pan came down, the technician found more ferrous metal debris than would be expected after only a four-mile road test. It was obvious that there was more damage inside the unit and it needed to be pulled out.

When the converter was removed, the input shaft remained in the converter. This is not abnormal, but what was strange was that the shaft could not be easily removed from the converter afterward. When the input shaft was eventually removed, the damage to its end (Figure 1) began to tell the story, and the damage found to the inside of the converter cover (Figure 2) told even more of the story. It was now obvious that the input shaft was protruding too far from the front of the transmission, but why was this happening?

A 2002 ATSG Tech Bulletin (02-20) was found that warned of the existence of two (2) different length input shafts. If you start back at theA4LD.shaft, there are actually three input shafts which have the same diameter and spline counts, but are different lengths. (Figure 3)

A4LD轴长,4-5R55E年代9-7/8”的措施haft (XL2Z-7017-AA) measures 10" long and the5R55 N, S and Wshafts (XW4Z-7017-AA) measure 10-1/4" long. Although there may be some long-term damage from insufficient tooth contact when using a shaft that is too short, the real danger comes from using a shaft that is too long. One inch is the proper distance that the input shaft should protrude from the stator support, (Figure 4) but 1-1/4" is too long. (Figure 5)

If the R&R technician was paying close attention, he would have realized that something was wrong. With the converter traditionally being bottomed out against the transmission during installation, it is normal for the converter to have to be pulled forward when attaching the flex plate bolts. This "stab depth" distance, normally .125" to .250" would have been zero in this situation because the shaft would have prevented the converter from moving as far in toward the unit as it normally would. If the R&R tech had noticed that the converter did not move forward, the shaft issue might have been caught before the damage was done.

Ed Lee is a Sonnax Technical Specialist who writes on issues of interest to torque converter rebuilders. Sonnax supports thebob游戏怎么下载Torque Converter Rebuilders协会.