Question about 2003 GMC Sierra 1500

1 Answer

Where is the thermostat located on my 2003 GMC Sierra truck? It's a 4.3 liter

Posted by on

1 Answer

  • Level 2:

    An expert who has achieved level 2 by getting 100 points


    An expert that gotĀ 5 achievements.


    An expert whose answer gotĀ voted for 20 times.


    An expert who has answered 20 questions.

  • Expert
  • 83 Answers

Follow the upper radiator hose to the engine.....Should be right behind the a/c compressor......It's under that housing.

Posted on Mar 17, 2011

1 Suggested Answer

  • 2 Answers

SOURCE: I have freestanding Series 8 dishwasher. Lately during the filling cycle water hammer is occurring. How can this be resolved

a 6ya expert can help you resolve that issue over the phone in a minute or two.
best thing about this new service is that you are never placed on hold and get to talk to real repairmen in the US.
the service is completely free and covers almost anything you can think of (from cars to computers, handyman, and even drones).
click here to download the app (for users in the US for now) and get all the help you need.

Posted on Jan 02, 2017

Add Your Answer

Uploading: 0%


Complete. Click "Add" to insert your video. Add



Related Questions:

1 Answer

What is the sparkplug firing order for GMC Sierra pickup truck with a 5.7 liter engine


Driver side cylinders, starting at the front of the engine, are 1,3,5,7

Passenger side, starting at the front, are ,2,4,6,8

Hope this helps.

Feb 24, 2015 | 2003 GMC Sierra 1500

1 Answer

How do i fix the Ignition Control Circuit High Voltage for 1996 GMC sierra 4.3 liter

Depending on the actual trouble code, the problem may be the ignition module inside the distributor or the coil.

Sep 11, 2014 | GMC Sierra 1500 Cars & Trucks

1 Answer

How to change thermostat on 2003 gmc sierra 5.3

Your not going to believe how easy it is to replace this one.

The thermostat is located behind the housing bolted to the water pump that the lower hose attaches to. remove the lower hose from the housing. Remove the 2 bolts holding the housing to the water pump with either a 10mm socket or wrench.

The new stat will come as a stat/housing assembly. bolt it on. Reattach the lower hose. Fill up the reservoir. Let the vehicle idle until up to operating temp making sure to keep the reservoir topped off while the engine warms up.

Mar 03, 2011 | 2003 GMC Sierra

3 Answers


Check this...
  1. Remove the air inlet duct.
  2. Drain the cooling system.
  3. Remove the radiator outlet hose.
  4. Remove the thermostat housing bolts.
  5. Remove the thermostat from the water pump housing.
NOTE The O-ring seal is integral to the thermostat housing


Fig. Thermostat housing - 4.8L, 5.3L and 6.0L engines (clikc image for zoom)

Hope helps (remember to rate this answer).

Dec 10, 2010 | 2002 GMC Sierra

2 Answers

I can not find location of Transmission kickdown solenoid for 1999 GMC Seirra 5.3 liter,4/4

this sensor is integral to the transmission. it is not an external serviceable item.

Aug 02, 2010 | 1999 GMC Sierra

1 Answer

Where's the oil filter located on a 1996 gmc sierra 4x4 ?

On a 5.3 liter engine it is located just in front of the flywheek housing on the drivers side.

Apr 10, 2010 | 1996 GMC Sierra

1 Answer

How to replace parking light on gmc 2003 1500 Sierra

open the hood and reach down to where the parking lights are located and give the plug in a 1/4 turn conterclockwise and the bulb should release from the lamp case. Then just remove the bulb from the plug that you gave a 1/4 turn to...and replace bulb. Then just put the bulb back in the casing and give a 1/4 turn clockwise to tighten. NO TOOLS REQUIRED

Jul 03, 2009 | 2003 GMC Sierra 1500

1 Answer

Oxygen sensor

Hello gobabygo1, my name is JShreader. Thank you for choosing

There is 4 Oxygen Sensors on this model Truck. I uploaded a picture showing you exactly where each of the 4 Oxygen Sensors are located. It is in .pdf format. You can download it by clicking HERE. I hope this helps you. If you have any more questions or need any more diagrams, please don't hesitate to ask...Thanks again, JShreader!

Mar 31, 2009 | 2003 GMC Sierra 1500

1 Answer


Right on top in the middle between the alternator and A/C compressor. The back t-stat has little vent holes that need to go towards the rear of the engine.

Jan 08, 2009 | 2003 GMC Sierra 2500HD

Not finding what you are looking for?
Cars & Trucks Logo

Related Topics:

286 people viewed this question

Ask a Question

Usually answered in minutes!

Top GMC Experts


Level 3 Expert

75197 Answers


Level 3 Expert

1311 Answers

Colin Stickland
Colin Stickland

Level 3 Expert

22095 Answers

Are you a GMC Expert? Answer questions, earn points and help others

Answer questions

Manuals & User Guides