Thermostat replacement...again
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Burning Brakes
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From: Hershey, PA
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Thermostat replacement...again
I replaced my thermostat with an OEM one 3 years ago because I was getting the tach lights. While driving the other night I noticed the tach lights are coming back well after the car is warmed up. I would think the thermostat would last longer than 3 years or is it normal to replace it this often? Or could I have another issue?
This is what I replaced it with.
This is what I replaced it with.
Instructor
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I will just say that for critical parts, I'll prefer to go to Rockauto or the dealer.
from Amazon I guess it depends where it comes from (from Amazon warehouse? From a reseller storage/ house?) And or, who is the seller, which is a second layer there.
wondering also where Amazon gets their parts... best bid? Authorized gm seller?
from Amazon I guess it depends where it comes from (from Amazon warehouse? From a reseller storage/ house?) And or, who is the seller, which is a second layer there.
wondering also where Amazon gets their parts... best bid? Authorized gm seller?
Last edited by PicaVette; Jun 8, 2026 at 08:42 PM.
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I replaced mine last year with that exact same item on Amazon.
IIRC it came in an AC Delco branded box.
IIRC it came in an AC Delco branded box.
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I have replaced the thermostat in my 2019 GS two times. The first was at 4K miles and again at 16k miles. AC Delco 15-11113 / GM 12674634 both times. The car was slow to warm up and the coolant temp would frequently drop below 176 F and trigger the yellow tach "halo." With a good thermostat the car warms up and mostly stays around 185 F in winter. Summer it obviously can go higher - up to maybe 210 F when stopped in traffic when it is 100 F and humid out.
I did not have to change the thermostat in my 2014 Z51 in the 21K miles I owned it.
Ron
I did not have to change the thermostat in my 2014 Z51 in the 21K miles I owned it.
Ron
Last edited by RonC7; Jun 8, 2026 at 10:43 PM.
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Have not replaced the thermostat on my 2014 but only have 10K miles on it. I would think that a thermostat should last longer than yours may have lasted.
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Your part may be genuine or not. There is no guarantee with Amazon even though the part does lean towards genuine.
Besides that point, thermostats seem to be almost luck nowadays on whether they will last or not. I have had one last a week and that was 30 years ago. Having one fail after only 3 years is not uncommon. Just get a new one and try to find a quality one. That's all you can do.
Besides that point, thermostats seem to be almost luck nowadays on whether they will last or not. I have had one last a week and that was 30 years ago. Having one fail after only 3 years is not uncommon. Just get a new one and try to find a quality one. That's all you can do.
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I've wondered the same thing, and I forgot to check the box when I last replaced my thermostat.
I asked the AI at Amazon where the item was manufactured ...
There was a study done on counterfeit spark plugs -- see https://www.thedrive.com/news/ridicu...hem-were-fakes
I would assume this could apply to other parts, or maybe the production QA is so low that there's no telling whether you get a good or bad thermostat.
I asked the AI at Amazon where the item was manufactured ...
The GM Genuine Parts Water Pump Outlet Assembly is manufactured by ACDelco, which is General Motors' parts division. It's a genuine OE (Original Equipment) part designed and engineered to GM factory specifications.
The product page doesn't specify the exact manufacturing location, but GM Genuine Parts and ACDelco parts are produced to meet GM's rigorous quality standards and are validated by General Motors for use in GM vehicles. Since you own a C7 Corvette, this is the OEM-equivalent replacement part designed specifically for your vehicle.
The product page doesn't specify the exact manufacturing location, but GM Genuine Parts and ACDelco parts are produced to meet GM's rigorous quality standards and are validated by General Motors for use in GM vehicles. Since you own a C7 Corvette, this is the OEM-equivalent replacement part designed specifically for your vehicle.
I would assume this could apply to other parts, or maybe the production QA is so low that there's no telling whether you get a good or bad thermostat.
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Burning Brakes
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I ended up buying one from my local Chevy dealer for $160. I'll replace it this weekend and hope for the best.
Thanks for the suggestions everyone!
Thanks for the suggestions everyone!
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I also agree that GM AC/Delco is the way to go
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I haven't replaced a thermostat in decades of owning GM Cars. The 2003 Tahoe I purchased brand new still has the original thermostat. My 2015 Z06 with 26K miles still has its original thermostat. Sometimes, thermostats are replaced when they aren't the problem. Sort of like O2 Sensors.
Bill
Bill
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Burning Brakes
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I haven't replaced a thermostat in decades of owning GM Cars. The 2003 Tahoe I purchased brand new still has the original thermostat. My 2015 Z06 with 26K miles still has its original thermostat. Sometimes, thermostats are replaced when they aren't the problem. Sort of like O2 Sensors.
Bill
Bill
