2016 Silverado 5.3 normal operating trans temp?

[Rickyace09]

My 5.3 has 66k and the transmission  has never been serviced. Truck drives fine but I notice a squeal or pitch noise that I think is coming from the trans. I also noticed it only starts after the temp gets around 180. Highest it has gotten that I noticed was 192 but dropped down to 190. Doesn’t sound like metal to metal just more like a low pitch. I have a scheduled appointment for next week to have it flushed but curious to what the normal temp should be. I’m also positive I never seen it climb past 175. 

Edited September 14, 2021 by Rickyace09

[CamGTP]

Normal temp is going to be around 180-200 degrees once fully warm. These transmission have a thermostat on them that will keep the temp up that high. A lot of guys will remove the thermostat so it runs 30-40 degrees cooler all the time.

[ftwhite]

Mine regularly hits 220+ on long road trips. No towing, no heavy loads, but usually outside air temp of 85+. This summer saw 110 outside temps get fluid to 240. Around town, short trips, I see 170-185. Dealer swaped fluid for studder problem. 

[elcamino]

If you added big tires that could change the shift patterns and be a reason for higher trans temps,  working harder etc.

[Logan Lanfear]

50 minutes ago, ftwhite said:

Mine regularly hits 220+ on long road trips. No towing, no heavy loads, but usually outside air temp of 85+. This summer saw 110 outside temps get fluid to 240. Around town, short trips, I see 170-185. Dealer swaped fluid for studder problem. 

Seems pretty high to me

[Rickyace09]

Truck is completely stock sound is similar to a radio sound 

[Larsson]

Gm runs very high transmission temperatures because of the thermostat that is used. normal operating temperature is round 190 degrees and gets higher when it's hot outside. Heat is a bad thing for automatic transmissions so first let it run a bit cooler .I fitted a superior solutions transmission thermostat. It keeps the transmission temperature round 150 degrees. 

 

The other thing to do is check if your transmission oil has metal flakes in it. if so, your in trouble and you proberally need to rebuild the transmission.