I have a 2013 Silverado 4l60e getting up to 210 has new fluid and filter has new radiator new thermostat and water pump and external transmission cooler in line with in radiator cooler when it gets up to 200 it slips and jerks when putting in gear I took it to transmission shop they say nothing is wrong I just keep throwing money at it with no result's truck has no codes has 120k miles I have a scanner that I can read live data on my scanner can someone plz guide me

 

What are you using to get your temp reading, an external temp sensor or a scanner that reads trans temp?

 

I am using the factory gate on the dash and looking at it on a scanner and with the infrared thermometer

 

How are you driving it when it starts to get hot? Highway, towing, stop and go. Is the converter locking up? Can you see trans slip with your scanner?

 

just around to alont of stop and go and my tc slip look normal even a good local transmission shop says transmission is working perfectly except overheating

 

You could unhook the return cooler line at the trans and run it into a bucket. Have someone start the truck and observe the how fast the fluid runs into the bucket. You could have an obduction somewhere in the cooler lines.