I have a 1993 chevy 1 ton dually with the 6.5L turbo diesel and a 4L80E transmission, I had the direct piston which was the cast aluminum break a cause me to seek out a transmission repair guy. I went with a fellow that does lot of the race transmissions locally and has a good reputation, he replaced the aluminum direct piston with a cast steel and rebuilt the transmission with new clutches, solenoids ect...... Now heres my blues, It will downshift out of OD into 3rd and will not shift back into OD until I have shut the key off and restarted, I informed the transmission guy and he said bring it back and I'll fix it, I brought it back and he did this to it,
(All new molded pistons, sonnax boost valve, accumulator block off plate, new bushings, new converter, vacuum checked valve body and pump, transgo separator plate, believe all solenoids are now swapped, filter, OD seals, new overrun sprag and intermediate sprag, both bands,) still no love but I do feel something like the lock up converter locking and unlocking now about every 20 to 30 seconds. Does anyone have any thoughts? Oh and the transmission guy is no longer doing transmissions on the side due to family concerns so he is not an option.
(All new molded pistons, sonnax boost valve, accumulator block off plate, new bushings, new converter, vacuum checked valve body and pump, transgo separator plate, believe all solenoids are now swapped, filter, OD seals, new overrun sprag and intermediate sprag, both bands,) still no love but I do feel something like the lock up converter locking and unlocking now about every 20 to 30 seconds. Does anyone have any thoughts? Oh and the transmission guy is no longer doing transmissions on the side due to family concerns so he is not an option.