ACDelco 12T121D | Engine Coolant Thermostat

Part Number

12T121D

Engine Coolant Thermostat

Fits: Buick Allure, Buick LaCrosse, Buick Rainier, Cadillac CTS, Cadillac Escalade, Cadillac Escalade ESV, Cadillac Escalade EXT, Chevrolet Avalanche 1500, Chevrolet Camaro, Chevrolet Corvette, Chevrolet Express 1500, Chevrolet Express 2500, Chevrolet Express 3500, Chevrolet Impala, Chevrolet Monte Carlo, Chevrolet Silverado 1500, Chevrolet Silverado 1500 HD, Chevrolet Silverado 2500, Chevrolet Silverado 2500 HD, Chevrolet Silverado 3500, Chevrolet Sonora, Chevrolet SSR, Chevrolet Suburban 1500, Chevrolet Suburban 2500, Chevrolet Tahoe, Chevrolet Trailblazer, Chevrolet Trailblazer EXT, Chevrolet W4500 Tiltmaster, GMC B6000, GMC B7, GMC C5000 Topkick, GMC C6000, GMC C6000 Topkick, GMC C6500 Topkick, GMC C7000, GMC C7000 Topkick, GMC C7500 Topkick, GMC Envoy, GMC Envoy XL, GMC Envoy XUV, GMC P6500, GMC Savana 1500, GMC Savana 2500, GMC Savana 3500, GMC Sierra 1500, GMC Sierra 1500 HD, GMC Sierra 2500

Special Price $25.12 Regular Price $29.55

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In stock

Estimated Ship Date: 1 Business Day or Less

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Details

187 Degrees Engine Coolant Thermostat with Gasket

BRAND: ACDelco

SPECIFICS:

ACD_RemanDes	No
AltPA_493_degrees_c	86
AltPA_493_degrees_f	187
Features & Benefits - B1	Controls the flow of coolant through the radiator to help your vehicle's engine reach and maintain its optimal operating temperature
Features & Benefits - B2	Professional, premium aftermarket replacement
Features & Benefits - B3	Provides the performance and dependability you expect from ACDelco
Features & Benefits - B4	Manufactured to meet expectations for fit, form, and function
Good Maintenance Practices - S1 B1	Have cooling system inspected immediately if instrument panel-mounted temperature gauge indicates engine overheating
Height	3.2
Length	3.5
Marketing Statement - Product Line	ACDelco has a full line of high-quality thermostats and caps for nearly all GM vehicles on the road today. Through our GM OE and Professional, premium aftermarket product lines, our thermostats cover a wide range of designs and temperature ratings to meet your needs. We also offer GM OE and Professional, premium aftermarket fuel caps, radiator caps, and oil filler/breather caps to replace your worn GM Original Equipment.
Marketing Statement - Sub Brand	When it comes to replacing your Thermostats and Caps, ACDelco offers a full line of Professional, premium aftermarket Thermostat and Cap products. In addition, ACDelco offers engine coolant thermostats, locking fuel caps, and standard type radiator caps to help make part replacement simple and precise. ACDelco Professional, premium aftermarket Thermostats and Caps fit both GM and Non GM vehicles.
Mkt_State_Warranty_CA	24 Months/40,000 KM (Parts Only). Please see ACDelcocanada.com for more details.
Mkt_State_Warranty_US	24 Month / Unlimited Mile Limited Warranty (Parts Only). Please see ACDelco.com for more details.
Product Description	ACDelco Professional Engine Coolant Thermostats control the flow of coolant through your vehicle's radiator to help the engine reach and maintain its optimal operating temperature, and are a high quality replacement for many vehicles on the road today. These engine coolant thermostats are manufactured to meet your expectations for fit, form, and function.
Programming Required	NO
Seal Type	Gasket
Signs of Wear & Troubleshooting - S1 B1	Coolant leaks
Signs of Wear & Troubleshooting - S1 B2	Engine overheating
Signs of Wear & Troubleshooting - S1 B3	Lack of available heat in the vehicle cabin
Signs of Wear & Troubleshooting - S1 H	Signs of wear for engine coolant thermostats include but are not limited to:
Vintage_Part_Indicator	N
Weight	.17
Width	3.2

DOWNLOADS:

APPLICATIONS:

2010-2012 Isuzu NPR

Temperature 187F Includes seal OEM Recommended Temp Standard

2000-2003 Chevrolet Suburban 2500

Temperature 187F Includes seal w/ Replacement late model water pump requiring seperate thermostat and housing. Thermostat only. OEM Recommended Temp Standard

1999-2003 Chevrolet Silverado 2500

Temperature 187F Includes seal w/ Replacement late model water pump requiring seperate thermostat and housing. Thermostat only. OEM Recommended Temp Standard

2003-2003 Chevrolet Express 1500

Temperature 187F Includes seal w/ Replacement late model water pump requiring seperate thermostat and housing. Thermostat only. OEM Recommended Temp Standard

2000-2003 Chevrolet Tahoe

Temperature 187F Includes seal w/ Replacement late model water pump requiring seperate thermostat and housing. Thermostat only. OEM Recommended Temp Standard

2004-2006 Cadillac Escalade

Temperature 187F Includes seal Thermostat only OEM Recommended Temp Standard

2003-2006 Chevrolet Trailblazer EXT

Temperature 187F Includes seal Thermostat only OEM Recommended Temp Standard

1990-1996 GMC C6000 Topkick

Temperature 187F Includes seal OEM Recommended Temp Standard

1997-1998 GMC C6500 Topkick

Temperature 187F Includes seal OEM Recommended Temp Standard

2004-2006 Chevrolet Avalanche 1500

Temperature 187F Includes seal Thermostat only OEM Recommended Temp Standard

1997-1998 GMC C7500 Topkick

Temperature 187F Includes seal OEM Recommended Temp Standard

1993-1998 GMC B7

Temperature 187F Includes seal OEM Recommended Temp Standard

2004-2006 GMC Savana 2500

Temperature 187F Includes seal Thermostat only OEM Recommended Temp Standard

2001-2003 GMC Sierra 3500

Temperature 187F Includes seal w/ Replacement late model water pump requiring seperate thermostat and housing. Thermostat only. OEM Recommended Temp Standard

2003-2006 Isuzu NPR-HD

Temperature 187F Includes seal OEM Recommended Temp Standard

2004-2004 GMC Sierra 2500

Temperature 187F Includes seal Thermostat only OEM Recommended Temp Standard

2004-2006 Pontiac GTO

Temperature 187F Includes seal Thermostat only OEM Recommended Temp Standard

2011-2012 Workhorse Custom Chassis W62

Temperature 187F Includes seal OEM Recommended Temp Standard

2004-2006 GMC Yukon XL 1500

Temperature 187F Includes seal Thermostat only OEM Recommended Temp Standard

2008-2009 Buick Allure

Temperature 187F Includes seal Thermostat only OEM Recommended Temp Standard

1997-1998 GMC T6500

Temperature 187F Includes seal OEM Recommended Temp Standard

2003-2003 GMC Savana 2500

Temperature 187F Includes seal w/ Replacement late model water pump requiring seperate thermostat and housing. Thermostat only. OEM Recommended Temp Standard

2004-2006 GMC Yukon XL 2500

Temperature 187F Includes seal Thermostat only OEM Recommended Temp Standard

2003-2003 Cadillac Escalade ESV

Temperature 187F Includes seal w/ Replacement late model water pump requiring seperate thermostat and housing. Thermostat only. OEM Recommended Temp Standard

2008-2009 Pontiac G8

Temperature 187F Includes seal Thermostat only OEM Recommended Temp Standard

2010-2010 GMC W4500 Forward

Temperature 187F Includes seal OEM Recommended Temp Standard

2004-2006 Chevrolet Silverado 2500 HD

Temperature 187F Includes seal Thermostat only OEM Recommended Temp Standard

2004-2006 Chevrolet Express 3500

Temperature 187F Includes seal Thermostat only OEM Recommended Temp Standard

1997-1998 GMC T7500

Temperature 187F Includes seal OEM Recommended Temp Standard

2004-2006 Hummer H2

Temperature 187F Includes seal Thermostat only OEM Recommended Temp Standard

2004-2004 Workhorse Custom Chassis P42

Temperature 187F Includes seal OEM Recommended Temp Standard

2004-2006 Cadillac Escalade ESV

Temperature 187F Includes seal Thermostat only OEM Recommended Temp Standard

2010-2011 Workhorse W62

Temperature 187F Includes seal OEM Recommended Temp Standard

2001-2003 Chevrolet Silverado 3500

Temperature 187F Includes seal w/ Replacement late model water pump requiring seperate thermostat and housing. Thermostat only. OEM Recommended Temp Standard

2006-2006 Chevrolet Express 3500

Temperature 187F Includes seal OEM Recommended Temp Standard

1999-2003 GMC Sierra 2500

Temperature 187F Includes seal w/ Replacement late model water pump requiring seperate thermostat and housing. Thermostat only. OEM Recommended Temp Standard

2003-2003 Chevrolet Express 3500

Temperature 187F Includes seal w/ Replacement late model water pump requiring seperate thermostat and housing. Thermostat only. OEM Recommended Temp Standard

2004-2006 Cadillac Escalade EXT

Temperature 187F Includes seal Thermostat only OEM Recommended Temp Standard

2005-2006 Chevrolet Silverado 1500 HD

Temperature 187F Includes seal Thermostat only OEM Recommended Temp Standard

2005-2008 Pontiac Grand Prix

Temperature 187F Includes seal Thermostat only OEM Recommended Temp Standard

2005-2008 Saab 9-7x

Temperature 187F Includes seal Thermostat only OEM Recommended Temp Standard

1990-1990 GMC C7000

Temperature 187F Includes seal OEM Recommended Temp Standard

2004-2006 Chevrolet Suburban 1500

Temperature 187F Includes seal Thermostat only OEM Recommended Temp Standard

2004-2005 GMC Envoy XUV

Temperature 187F Includes seal Thermostat only OEM Recommended Temp Standard

2002-2003 Cadillac Escalade EXT

Temperature 187F Includes seal w/ Replacement late model water pump requiring seperate thermostat and housing. Thermostat only. OEM Recommended Temp Standard

2004-2006 Chevrolet Sonora

Temperature 187F Includes seal Thermostat only OEM Recommended Temp Standard

2001-2003 GMC Sierra 2500 HD

Temperature 187F Includes seal w/ Replacement late model water pump requiring seperate thermostat and housing. Thermostat only. OEM Recommended Temp Standard

2002-2003 Chevrolet Avalanche 1500

Temperature 187F Includes seal w/ Replacement late model water pump requiring seperate thermostat and housing. Thermostat only. OEM Recommended Temp Standard

1992-1996 GMC P6500

Temperature 187F Includes seal OEM Recommended Temp Standard

2001-2003 Chevrolet Silverado 2500 HD

Temperature 187F Includes seal w/ Replacement late model water pump requiring seperate thermostat and housing. Thermostat only. OEM Recommended Temp Standard

2004-2007 Cadillac CTS

Temperature 187F Includes seal Thermostat only OEM Recommended Temp Standard

2002-2003 Cadillac Escalade

Temperature 187F Includes seal w/ Replacement late model water pump requiring seperate thermostat and housing. Thermostat only. OEM Recommended Temp Standard

2004-2006 Chevrolet Express 1500

Temperature 187F Includes seal OEM Recommended Temp Standard

1999-2003 Chevrolet Silverado 1500

Temperature 187F Includes seal w/ Replacement late model water pump requiring seperate thermostat and housing. Thermostat only. OEM Recommended Temp Standard

2005-2006 GMC Sierra 1500 HD

Temperature 187F Includes seal Thermostat only OEM Recommended Temp Standard

2004-2006 Chevrolet Silverado 3500

Temperature 187F Includes seal Thermostat only OEM Recommended Temp Standard

1990-1991 GMC B6000

Temperature 187F Includes seal OEM Recommended Temp Standard

2000-2003 Chevrolet Suburban 1500

Temperature 187F Includes seal w/ Replacement late model water pump requiring seperate thermostat and housing. Thermostat only. OEM Recommended Temp Standard

2004-2006 GMC Sierra 2500 HD

Temperature 187F Includes seal Thermostat only OEM Recommended Temp Standard

2003-2003 GMC Envoy XL

Temperature 187F Includes seal w/ Replacement late model water pump requiring seperate thermostat and housing. Thermostat only. OEM Recommended Temp Standard

2003-2003 Hummer H2

Temperature 187F Includes seal w/ Replacement late model water pump requiring seperate thermostat and housing. Thermostat only. OEM Recommended Temp Standard

2006-2006 Chevrolet Trailblazer

Temperature 187F Includes seal Thermostat only OEM Recommended Temp Standard

2004-2006 Chevrolet Suburban 2500

Temperature 187F Includes seal Thermostat only OEM Recommended Temp Standard

1997-2003 Chevrolet Corvette

Temperature 187F Includes seal w/ Replacement late model water pump requiring seperate thermostat and housing. Thermostat only. OEM Recommended Temp Standard

2004-2006 Buick Rainier

Temperature 187F Includes seal Thermostat only OEM Recommended Temp Standard

2005-2006 GMC Envoy

Temperature 187F Includes seal Thermostat only OEM Recommended Temp Standard

2004-2006 Chevrolet Tahoe

Temperature 187F Includes seal Thermostat only OEM Recommended Temp Standard

2001-2003 Chevrolet Silverado 1500 HD

Temperature 187F Includes seal w/ Replacement late model water pump requiring seperate thermostat and housing. Thermostat only. OEM Recommended Temp Standard

2000-2003 GMC Yukon XL 1500

Temperature 187F Includes seal w/ Replacement late model water pump requiring seperate thermostat and housing. Thermostat only. OEM Recommended Temp Standard

2004-2006 GMC Sierra 1500

Temperature 187F Includes seal Thermostat only OEM Recommended Temp Standard

2003-2003 GMC Savana 1500

Temperature 187F Includes seal w/ Replacement late model water pump requiring seperate thermostat and housing. Thermostat only. OEM Recommended Temp Standard

2001-2003 GMC Sierra 1500 HD

Temperature 187F Includes seal w/ Replacement late model water pump requiring seperate thermostat and housing. Thermostat only. OEM Recommended Temp Standard

2004-2006 GMC Yukon

Temperature 187F Includes seal Thermostat only OEM Recommended Temp Standard

1998-2002 Pontiac Firebird

Temperature 187F Includes seal w/ Replacement late model water pump requiring seperate thermostat and housing. Thermostat only. OEM Recommended Temp Standard

2003-2003 Chevrolet Express 2500

Temperature 187F Includes seal w/ Replacement late model water pump requiring seperate thermostat and housing. Thermostat only. OEM Recommended Temp Standard

2003-2003 GMC Savana 3500

Temperature 187F Includes seal w/ Replacement late model water pump requiring seperate thermostat and housing. Thermostat only. OEM Recommended Temp Standard

2010-2010 Chevrolet W4500 Tiltmaster

Temperature 187F Includes seal OEM Recommended Temp Standard

2004-2009 Chevrolet Silverado 2500

Temperature 187F Includes seal Thermostat only OEM Recommended Temp Standard

2000-2003 GMC Yukon XL 2500

Temperature 187F Includes seal w/ Replacement late model water pump requiring seperate thermostat and housing. Thermostat only. OEM Recommended Temp Standard

2004-2006 GMC Savana 3500

Temperature 187F Includes seal Thermostat only OEM Recommended Temp Standard

2000-2003 GMC Yukon

Temperature 187F Includes seal w/ Replacement late model water pump requiring seperate thermostat and housing. Thermostat only. OEM Recommended Temp Standard

1999-2003 GMC Sierra 1500

Temperature 187F Includes seal w/ Replacement late model water pump requiring seperate thermostat and housing. Thermostat only. OEM Recommended Temp Standard

1998-2002 Chevrolet Camaro

Temperature 187F Includes seal w/ Replacement late model water pump requiring seperate thermostat and housing. Thermostat only. OEM Recommended Temp Standard

2003-2003 Chevrolet SSR

Temperature 187F Includes seal w/ Replacement late model water pump requiring seperate thermostat and housing. Thermostat only. OEM Recommended Temp Standard

2006-2007 Chevrolet Monte Carlo

Temperature 187F Includes seal Thermostat only OEM Recommended Temp Standard

2004-2006 Isuzu Ascender

Temperature 187F Includes seal Thermostat only OEM Recommended Temp Standard

2004-2006 Chevrolet Express 2500

Temperature 187F Includes seal Thermostat only OEM Recommended Temp Standard

2006-2009 Chevrolet Impala

Temperature 187F Includes seal Thermostat only OEM Recommended Temp Standard

1990-1996 GMC C7000 Topkick

Temperature 187F Includes seal OEM Recommended Temp Standard

2003-2003 Isuzu Ascender

Temperature 187F Includes seal w/ Replacement late model water pump requiring seperate thermostat and housing. Thermostat only. OEM Recommended Temp Standard

1990-1991 GMC C5000 Topkick

Temperature 187F Includes seal OEM Recommended Temp Standard

2004-2008 Chevrolet Corvette

Temperature 187F Includes seal Thermostat only OEM Recommended Temp Standard

2001-2003 Chevrolet Sonora

Temperature 187F Includes seal w/ Replacement late model water pump requiring seperate thermostat and housing. Thermostat only. OEM Recommended Temp Standard

1990-1990 GMC C6000

Temperature 187F Includes seal OEM Recommended Temp Standard

2003-2006 Isuzu NPR

Temperature 187F Includes seal OEM Recommended Temp Standard

2004-2006 GMC Envoy XL

Temperature 187F Includes seal Thermostat only OEM Recommended Temp Standard

2004-2006 Chevrolet SSR

Temperature 187F Includes seal Thermostat only OEM Recommended Temp Standard

2004-2006 GMC Savana 1500

Temperature 187F Includes seal Thermostat only OEM Recommended Temp Standard

2008-2009 Buick LaCrosse

Temperature 187F Includes seal Thermostat only OEM Recommended Temp Standard

2004-2006 GMC Sierra 3500

Temperature 187F Includes seal Thermostat only OEM Recommended Temp Standard

2004-2006 Chevrolet Silverado 1500

Temperature 187F Includes seal Thermostat only OEM Recommended Temp Standard

Product Questions (7)

Customer Questions

Does AC Delco make Ford parts?

No, AC Delco produces parts primarily for General Motors vehicles and does not make parts specifically for Ford vehicles.

Can I use AC Delco parts to replace OEM parts?

Yes, in most cases AC Delco parts can be used as a replacement for OEM parts. However, it's important to ensure that the parts are compatible with your specific make and model of vehicle.

What AC Delco oil filter do I need?

AC Delco offers a variety of oil filters that are compatible with different makes and models of vehicles. To determine which AC Delco oil filter you need, consult your vehicle's owner's manual or use our online filter lookup tool that matches the make, model, and year of your vehicle.

When to replace the engine coolant thermostat?

The engine coolant thermostat should be replaced if it is not functioning properly or as a preventive maintenance measure after a certain mileage or time interval.

What is an engine coolant thermostat?

An engine coolant thermostat is a component that regulates the flow of coolant through the engine to maintain optimal operating temperature.

Will the engine coolant temperature sensor keep the car from starting?

In most cases, a malfunctioning engine coolant temperature sensor (ECT sensor) will not prevent the car from starting. The engine coolant temperature sensor (ECT sensor) is responsible for monitoring the temperature of the engine coolant and sending that information to the engine control unit (ECU). The ECU uses this information to make adjustments to the fuel mixture and ignition timing for optimal engine performance.

Does PartsHawk carry an engine coolant thermostat for Mazda 6?

Yes, PartsHawk carries an Engine Coolant thermostat for Mazda 6