2014 Silverado 6l80 Slipping/Shudder

[Wyat Weir]

I know this has been addressed a thousand times, however, needing some concrete advice from knowledgeable people. I will start off by saying I am a complete idiot.
 

Around 110,000 miles, I started to experience what I thought was a shutter from the torque converter. There were no codes thrown at all. I brought it to a transmission shop, they told me I needed to replace the torque converter and they did.

 

This is why I am a complete idiot. The “Shutter” was still ongoing after replacement. That “shutter” ended up being a slight misfire, as I replaced all of my spark plug wires and that fixed my problem! 

 

About 1,000 miles after having the torque converter replaced is when I learned what a torque converter shutter really was; loud vibration as if driving over rumble strips on the road. Tachometer jumping up about 250 rpm’s, then coming back down while cruising. Gears 3 and 4 slipping. Never had any of these issue before the converter replacement. 
 

I brought it back to the transmission shop. They changed the fluid and added a shutter stop additive and that didn’t change a thing. Told me to f*** off after that basically. 

 

How did that transmission shop royally screw up my transmission? Inferior parts? No friction modifier? Do you have to reflash the TCM after replacing the torque converter? 
 

I’m looking into buying rebuilt 6l80s or trying to find a good shop that could rebuild mine, however, am just skeptical. I’m located in South Texas 

[Snowcamo]

Your issue is not the convertor. It is the trans oil pump that is right behind the convertor. Sends less fluid throughout the trans. Burns the clutch packs.Time for a full rebuild. 

 

I'm in north Texas and can highly recommend my trans builder. Will cost you less the what the going rate is and be upgraded with new upgrade valves, thermostat bypass and so on. If you decide to come up this way let me know.

Edited July 31, 2023 by Snowcamo