Recommended replacement interval for the part category Thermostat : 50000 km

Important!

This replacement procedure can be used for:
AUDI A6 Allroad (4FH, C6) 4.2 FSI quattro … View more

The steps may slightly vary depending on the car design.

This video shows the replacement procedure of a similar car part on another vehicle

Alternative products

Thermostat

Replacement: engine thermostat – AUDI A6 Allroad (4FH, C6). Tools you might need:

                      Torque wrench
                    
                      Drive socket # 7 
                    
                      Drive socket # 10 
                    
                      Drive socket # 13 
                    
                      Ratchet wrench
                    
                      Fluid container
                    
                      Funnel
                    
                      Fender cover

Buy tools

Replacement: engine thermostat – AUDI A6 Allroad (4FH, C6). Tip from AUTODOC:

Check the condition of the coolant every time you replace the thermostat. Change the coolant if necessary.
Please note: all work on the car – AUDI A6 Allroad (4FH, C6) – should be done with the engine switched off.

Carry out replacement in the following order:

Step 1

Open the hood.

Step 2

Use a fender protection cover to prevent damaging paintwork and plastic parts of the car.

Step 3

Unscrew the coolant reservoir cap.
Step 4

Prepare a container for fluids.
Step 5

Loosen the coolant hose clamp. Use a drive socket #7. Use a ratchet wrench.
Step 6

Detach the coolant hose.
Step 7

Drain the coolant from the engine.

Replacement: engine thermostat – AUDI A6 Allroad (4FH, C6). Tip:
Caution! The coolant can be very hot.Wear gloves to prevent contact with hot liquid.All work should be done with the engine stopped.Wait until the coolant has completely flowed out of the drain hole.
Step 8

Unscrew the thermostat housing fasteners. Use a drive socket #13. Use a ratchet wrench.
Step 9

Remove the thermostat housing.

AUTODOC recommends:
Replacement: engine thermostat – AUDI A6 Allroad (4FH, C6). Do not use excessive force when removing the part as this may damage it.
Step 10

Remove the thermostat.

AUTODOC recommends:
Replacement: engine thermostat – AUDI A6 Allroad (4FH, C6). Do not use excessive force when removing the part as this may damage it.Caution! Coolant may leak out of the coolant lines and thermostat housing.
Step 11

Install a new thermostat.

Replacement: engine thermostat – AUDI A6 Allroad (4FH, C6). Tip:
When installing, do not use excessive force to avoid damage to the part.
Step 12

Install the thermostat housing.
Step 13

Tighten the thermostat housing fasteners. Use a drive socket #10. Use a torque wrench. Tighten it to 13 nm torque.
Step 14

Attach the coolant hose.
Step 15

Secure the coolant hose clamp. Use a drive socket #7. Use a ratchet wrench.
Step 16

Remove the coolant reservoir cap.

Step 17

Insert the funnel.
Step 18

Pour coolant in the coolant reservoir.

Replacement: engine thermostat – AUDI A6 Allroad (4FH, C6). Tip from AUTODOC:
Only use the coolant recommended by the manufacturer.The coolant level should be at the MAX mark.Wait until the air goes out of the system.
Step 19

Run the engine for a few minutes. This should be done in order to remove residual air from the cooling system and to check if the components are operating correctly.

Step 20

Shut off the engine.

Step 21

Install the coolant reservoir cap.

Step 22

Screw on the coolant reservoir cap.

Step 23

Remove the fender protection cover.

Step 24

Close the hood.

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