2015 Silverado 6.2l Low Trans Temp

truckguy82 · July 3, 2018

guys it's very easy to test the trans thermostat

all you need to do is feel the trans cooler exit line, it's a metal line.

It should be ambient temp until the trans is 190 degrees. Then it allows flow and gets scorching hot.

So if your line is hot after 15 minutes of driving, then your thermostat is stuck open.

Mine was cold all the time because it was stuck closed.

Dealership failed miserably at diagnosing this, I had to do all the diagnosis myself and finally tell them my thermostat is not working.

Bryn7471 · July 4, 2018

Well the guy at the dealership took it for a test ride with me and noticed immediately. He said it’s the torque converter shutter and the first step is getting the transmission flushed 3 times as per GM’s procedure for the fix. Then I have to drive it around for at least 250 miles after that’s done to see if it fixes the issue. If it doesn’t then they will swap out the torque converter at that point. I also explained to him about the thermostat and he saw that it was around 130. He seemed to think it was normal after driving all the way from work for 30 minutes. I finally convinced him that it will need to be changed out after I showed him pictures from the other morning. Can’t be colder than ambient air temp! So I will be bringing the truck in Friday morning to have the flush done. Hopefully this fixes it!

Bryn7471 · July 8, 2018

We’ll I got the truck back on Friday evening and for the first 20 miles I didn’t have any issues. Since then it has happened 3 more times and Ive gone about 130 miles now since the “fix”. I have to wait until after 250 miles according to the tech and if it’s still an issue, then it will get a new torque converter. So at this point I will just keep putting miles on it until then... Then back in the shop again.

300 Blackout · September 16, 2018

How did this all work out?

Bryn7471 · September 17, 2018

Well It continues to do it every 3-4 days. Brought it back to the dealer and of course he couldn’t make it do it while he drove it for 3 minutes. So they told me there is nothing they can do until it does it for them. Problem is they would have to keep it for a week before they would feel it, so that’s going to be tough. For now I am waiting until the vibration gets bad again so I know I can make it reproduce for them again. I even had a Case number with chevy but all they did was open a case number, talk to the dealer, and come to the same conclusion. It’s been very frustrating.

m3n00b · June 14, 2019

On 6/26/2018 at 4:13 PM, Bryn7471 said:

I've noticed something very similar the other morning. My trans temp was 45 and ambient was 65. This was at 4AM before the sun came up. It never dropped below 60 that night. I don't think these sensors are accurate at all.