Issue with 2017 Tahoe Coolant Temperature

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2017tahoecb

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Hi All,

Looking for some help here with a weird problem i'm having. About a month ago my Tahoe randomly had its radiator fan turn on while driving in cold weather (30-40 degree) and not shut off, in addition, the coolant temp would not come above the lowest temp mark on the gauges.

I replaced the coolant temp sensor, and restarted the vehicle and the fan was off and it seemed the coolant temp was now heating up (at least more than the very minimum)

Now, the coolant temp very rarely ever reaches the middle mark for operating temp, it normally only reaches midway between cold and operating temp. We have driven multiple 6hr road trips since then and it almost never has reached operating temp.

Is this a basic thermostat issue? Bad coolant temp sensor? Any advice is greatly appreciated.
 
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B-train

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Have you felt the upper hose by hand after driving over or used a temp gun to check it? How's the heat inside?

My 2017 started hanging around 175 for about 2 months. After a previous post I read, I replaced the thermostat and Viola! I had 210F again. The new thermostat appears to be a 2 stage opening. I found that on the original one, the smaller spring portion wasn't closing all the way. Super easy job. You'll need 2 gallons to replace what comes out. Way nicer to replace than the previous generation.

Torque on install is 12ft-lbs or 144 in/lbs depending on what size torque wrench you use. Might want to Google it just to double check, they are small bolts. Has a really nice o-ring gasket, just clean up the mounting surface if there is residue from the original.
 

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Mando6point2

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Agree on Thermostat replacement. Seems on the chevys the temp sensor and thermostat always go right behind eachother. Thermostat fixed a silverado with same issue after a temp sensor replacement
 
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2017tahoecb

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Hi All,

Looking for some help here with a weird problem i'm having. About a month ago my Tahoe randomly had its radiator fan turn on while driving in cold weather (30-40 degree) and not shut off, in addition, the coolant temp would not come above the lowest temp mark on the gauges.

I replaced the coolant temp sensor, and restarted the vehicle and the fan was off and it seemed the coolant temp was now heating up (at least more than the very minimum)

Now, the coolant temp very rarely ever reaches the middle mark for operating temp, it normally only reaches midway between cold and operating temp. We have driven multiple 6hr road trips since then and it almost never has reached operating temp.

Is this a basic thermostat issue? Bad coolant temp sensor? Any advice is greatly appreciated.
Thank you both for your replies, I will try thermostat and go from there.
 

mrathell

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Changing the thermostat work for me. I was having the exact same issue as you. Just make sure your replacement thermostat isn't one of those ones that are designed to open at a lower temperature.

Here is a video I made of me replacing my thermostat:

 
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2017tahoecb

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Changing the thermostat work for me. I was having the exact same issue as you. Just make sure your replacement thermostat isn't one of those ones that are designed to open at a lower temperature.

Here is a video I made of me replacing my thermostat:

Fantastic video, Sir! Ill be doing this today after work. Thank you!
 

iksplizit

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Have you felt the upper hose by hand after driving over or used a temp gun to check it? How's the heat inside?

My 2017 started hanging around 175 for about 2 months. After a previous post I read, I replaced the thermostat and Viola! I had 210F again. The new thermostat appears to be a 2 stage opening. I found that on the original one, the smaller spring portion wasn't closing all the way. Super easy job. You'll need 2 gallons to replace what comes out. Way nicer to replace than the previous generation.

Torque on install is 12ft-lbs or 144 in/lbs depending on what size torque wrench you use. Might want to Google it just to double check, they are small bolts. Has a really nice o-ring gasket, just clean up the mounting surface if there is residue from the original.
Which one did you get and where did you pick it up from? My local parts store said they don't have it and would need to order it from the dealer
 

B-train

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I just ordered mine from VALLEYPARTS.COM

It's and online GM parts store. Good pricing and quick shipping.
 

SJ_Tahoe

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Watching this thread, great info!
Does anyone know where I can see my watched threads on the site?
 
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