RedVenom48
Newbie
Success!!! We have shifting! All 4 forward speeds and reverse!!! Looks like the little voice in my head that told me to replace the solenoids and pressure switches with the pan off was right.
In total I replaced the following:
1 Input shaft speed sensor (genuine GM)
1 Internal trans harness (NAPA, made by Rostra)
2 Shift Solenoids: 1-2 and 2-3 (Genuine GM)
1 Pressure switch pad (Genuine GM)
1 Torque Converter Solenoid (Carquest)
1 Trans pan gasket (Amazon China special ...will probably leak later haha)
5 quarts of ATF (Valvoline max life Dexron compatible)
Again, this was to fix a reverse and 2nd gear only condition, NO DTCs. Shift 1-2 was failed open, Shift 2-3 was below spec on resistance. TCC solenoid ohm'ed ok as well as the Pressure control solenoid. I dont have a way to adjust pressure so I rolled with the installed Pressure control solenoid.
Amazingly enough, the transmission shifts very smoothly. Much better than I anticipated it would given what its been through and having 195k on the clock. To be clear this is with just me in the Burban, ambient temps in the 70s driving on the street. Will take her on the freeway later to see how it does. Ive also got my 73 Nova hanging out at a buddies house that I need to get, so that should be a decent test for towing.
Frankly, I've got no expectations going forward. My hope is that the robustness the 4L80 is famous for translates to my specific Suburban. The Carfax did show frequent servicing, so my hope is the internals have some decent life left in them before a true rebuild will be needed. I bought this thing for $1000 bucks, and while she's.... rough inside, if she is mechanically solid thats all I can really ask for.
In total I replaced the following:
1 Input shaft speed sensor (genuine GM)
1 Internal trans harness (NAPA, made by Rostra)
2 Shift Solenoids: 1-2 and 2-3 (Genuine GM)
1 Pressure switch pad (Genuine GM)
1 Torque Converter Solenoid (Carquest)
1 Trans pan gasket (Amazon China special ...will probably leak later haha)
5 quarts of ATF (Valvoline max life Dexron compatible)
Again, this was to fix a reverse and 2nd gear only condition, NO DTCs. Shift 1-2 was failed open, Shift 2-3 was below spec on resistance. TCC solenoid ohm'ed ok as well as the Pressure control solenoid. I dont have a way to adjust pressure so I rolled with the installed Pressure control solenoid.
Amazingly enough, the transmission shifts very smoothly. Much better than I anticipated it would given what its been through and having 195k on the clock. To be clear this is with just me in the Burban, ambient temps in the 70s driving on the street. Will take her on the freeway later to see how it does. Ive also got my 73 Nova hanging out at a buddies house that I need to get, so that should be a decent test for towing.
Frankly, I've got no expectations going forward. My hope is that the robustness the 4L80 is famous for translates to my specific Suburban. The Carfax did show frequent servicing, so my hope is the internals have some decent life left in them before a true rebuild will be needed. I bought this thing for $1000 bucks, and while she's.... rough inside, if she is mechanically solid thats all I can really ask for.