The thermostat housing is located in the engine between the engine and the radiator. When the engine cools off below the operating temperature, the thermostat housing is closed.
The common symptoms of a thermostat housing leak are a stuck thermostat valve, an illuminated low coolant warning light, and the P0128 or P0125 code.
If the thermostat housing is broken or leaking fluid, it needs to be replaced as soon as you can.

Compatible with Buick 4.2L L6 Vehicles:
2004-2007 Rainier

Compatible with Chevy 4.2L L6 Vehicles:
2002-2009 Trailblazer
2002-2006 Trailblazer EXT

Compatible with GMC 4.2L L6 Vehicles:
2002-2009 Envoy
2002-2006 Envoy XL
2004-2005 Envoy XUV

Compatible with Isuzu 4.2L L6 Vehicles:
2003-2008 Ascender

Compatible with Oldsmobile 4.2L L6 Vehicles:
2002-2004 Bravada

Compatible with Saab 4.2L L6 Vehicles:
2005-2009 Saab 9-7x

Replaces Part #: 902-800, 15-11006, 1511006 Engine Coolant Thermostat Housing Assembly.

NOTE: This is NOT a genuine part, it's a aftermarket replacement part manufactured by Allmotorparts.

NOTE: To ensure accurate fitment, please confirm your vehicle information in the above compatibility section and the description.