Mercedes-Benz S450 Car Thermostat Replacement at your home or office.

Our mobile mechanics offer services 7 days a week. Upfront and transparent pricing.

Estimate price near me

Service Location

Customer Ratings

(70)

Included for free with this service

Online Booking

Mechanic comes to you

12-month / 12k-mile warranty

Free 50 point safety inspection

Our certified mobile mechanics can come to your home or office 7 days a week between 7 AM and 9 PM.

Customer Ratings

(70)

Car Thermostat Replacement Service

How much does a Car Thermostat Replacement cost?

On average, the cost for a Mercedes-Benz S450 Car Thermostat Replacement is $405 with $209 for parts and $196 for labor. Prices may vary depending on your location.

CarServiceEstimateShop/Dealer Price
2009 Mercedes-Benz S450V8-4.7LService typeCar Thermostat ReplacementEstimate$697.38Shop/Dealer Price$808.46 - $1127.10
2008 Mercedes-Benz S450V8-4.7LService typeCar Thermostat ReplacementEstimate$681.16Shop/Dealer Price$789.06 - $1105.32
2010 Mercedes-Benz S450V8-4.7LService typeCar Thermostat ReplacementEstimate$681.16Shop/Dealer Price$789.10 - $1105.40
2011 Mercedes-Benz S450V8-4.7LService typeCar Thermostat ReplacementEstimate$681.16Shop/Dealer Price$789.10 - $1105.39
2018 Mercedes-Benz S450V6-3.0L TurboService typeCar Thermostat ReplacementEstimate$906.33Shop/Dealer Price$1086.47 - $1616.43
Show example Mercedes-Benz S450 Car Thermostat Replacement prices

What is an engine cooling system thermostat and how does it work?

The car's engine cooling system thermostat is a small valve within a cooling system passageway that opens and closes in response to the temperature of the circulating engine coolant. When your car is first started and the coolant is cold, the valve in the thermostat will be in the closed position, circulating the coolant flow only within the engine instead of flowing to the radiator, which allows the engine to warm up fast, promoting fuel efficiency, low emissions, and reduced engine deposits. Once the engine coolant reaches the design temperature, usually around 195 degrees, the valve will open and close as you drive in order to maintain a coolant temperature typically between 195 to 225 degrees Fahrenheit.

Thermostat

When to consider replacing the engine cooling system thermostat:

  • Engine overheats. A thermostat with the valve stuck closed is a common cause of engine overheating. However, since there are other causes of overheating, a mechanic will thoroughly inspect the cooling system prior to condemning the thermostat. Since it is usually not known how badly the engine overheated, the mechanic will also try to determine if there is evidence that the cylinder head gasket was blown. If so, it would be repaired prior to replacing the thermostat.
  • Temperature gauge reads too low or too high. Thermostats can get sticky, causing the engine temperature to stray from the optimal range. Your dash-mounted temperature gauge will notify you of this malfunction.
  • Cooling system repairs. All thermostats eventually fail. Therefore, if the cooling system is already open for major repairs, such as water pump or radiator replacement, it is recommended to install a new thermostat simply as insurance against future breakdown.

How do mechanics replace the engine cooling system thermostat?

  • Once the engine is completely cold, the radiator cap is loosened and enough coolant is drained from the radiator so the coolant level is below the thermostat housing.
  • The thermostat housing is removed and the thermostat and gasket are extracted. Note that some cars have more than one cooling system thermostat and both might need replacement.
  • All mounting surfaces on the thermostat housing are cleaned of old gasket material. A new gasket is applied and the thermostat is re-installed in the correct orientation and with the temperature sensing cylinder facing downward towards the engine.
  • The thermostat housing bolts are tightened to original equipment manufacturer (OEM) specifications using a calibrated inch-pound torque wrench.
  • The cooling system is refilled with the appropriate coolant type and the system is fully bled of all air.
  • The car engine is run until the normal operating temperature is reached, and while taking precautions with the hot coolant, the coolant level is rechecked while confirming there is flow through the radiator — either visually or with an infrared temperature gun. This will confirm the thermostat is open. Finally, the engine is checked for leaks.

Is it safe to drive with an engine cooling system thermostat problem?

No. If it has been determined that there is a thermostat problem, it should be repaired right away. Failure to do so can cause substantial and costly damage to the engine.

When replacing the engine cooling system thermostat keep in mind:

  • Engine overheating due to causes other than a faulty thermostat, will themselves damage a thermostat. Therefore, always replace the thermostat if the engine overheats, even if the thermostat was not the initial cause of the overheating.
  • The thermostat should be replaced anytime you have major work done on the coolant system. It is convenient and costs little during such repairs and insurance against future breakdown.
  • OEM thermostats are the best ones to use and you can request your mechanic to install only the OEM thermostat. Dealer supplied, OEM thermostats are sometimes more costly but are generally higher quality and specifically engineered for your car.

Fast and easy service at your home or office

Backed by 12-month, 12.000-mile guarantee


Meet some of our expert Mercedes-Benz mechanics

Real customer reviews from Mercedes-Benz owners like you.

Excellent Rating

(70)

Rating Summary
66
2
0
0
2
66
2
0
0
2

Tinashe

14 years of experience
781 reviews
Tinashe
14 years of experience
Mercedes-Benz S450 V6-3.0L Turbo - Turo Host Inspection - Atlanta, Georgia
Amazing guy and very thorough. Best guy for the job 

Ricardo

15 years of experience
339 reviews
Ricardo
15 years of experience
Mercedes-Benz S450 V6-3.0L Turbo - Pre-purchase Car Inspection - Culver City, California
Ricardo is very trustworthy, responsible, on time for the service , and fast reply.

Kenneth

21 years of experience
870 reviews
Kenneth
21 years of experience
Mercedes-Benz S450 V6-3.0L Turbo - Pre-purchase Car Inspection - Los Angeles, California
Kenneth is very friendly and easy to work with.

Scott

37 years of experience
995 reviews
Scott
37 years of experience
Mercedes-Benz SL500 V8-5.0L - Thermostat - San Tan Valley, Arizona
He again has taken care of one of my vehicles in the same manner as he always does. Excellent, Professional and will find answers and not give up. Thanks again, Scott.

Excellent Rating

(70)

Rating Summary
66
2
0
0
2
66
2
0
0
2
Number of Mercedes-Benz Car Thermostat Replacement services completed
770+
services done by our mechanics
TOTAL NUMBER OF EXPERT Mercedes-Benz MECHANICS
1100+
experts on our platform

Recent articles & questions

P2148 OBD-II Trouble Code: Fuel Injector Group A Supply Voltage Circuit High
What What the P2148 code means? P2148 is an OBD-II generic code for the engine control module (ECM) detecting the fuel injector group A supply voltage circuit has a high resistance causing a short in the system. What causes the...
The Guide To Colored Curb Zones in Texas
Texas Texas parking laws: understanding the basics Driving in Texas requires drivers to pay attention to their surroundings and to the laws of the road. This does not stop just because you are parking your vehicle. In fact, if you...
How Long Does an AC High Pressure Hose Last?
Your Your car’s AC system works very much like your home’s air conditioning in that it uses a refrigerant to hold heat and then to deliver cool air. Depending on the amount of pressure the refrigerant is under, it will...

How do I use the Timer feature in the driver information center (DIC)?

The Timer feature in the driver information center (DIC) allows you to set a timer through the DIC display. To use the timer, follow these instructions: 1. Press the MENU button until the DIC displays Trip/Fuel Information Menu. 2. Use...

I change my oil change oil filter fuel pump and filter spark plugs and wires distruibor cab and rotor. Truck shakes why?

If your Check Engine Light is coming on, a fault code should be stored in the ECM. A flashing Check Engine Light indicates a potentially serious engine failure. Since the situation you are experiencing can be caused by any number...

do you service ozone park, new your

Hi there. In order to provide you an accurate quote and verify we service your area, please submit a request for an oil / filter change (https://www.yourmechanic.com/services/change-oil-and-filter) and we'll send you a quote.

How can we help?

Our service team is available 7 days a week, Monday - Friday from 6 AM to 5 PM PST, Saturday - Sunday 7 AM - 4 PM PST.

1 (855) 347-2779 · hi@yourmechanic.com