Mercedes-Benz S420 Car Thermostat Replacement at your home or office.

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Car Thermostat Replacement Estimate for Mercedes-Benz S420

Mercedes-Benz S420 Car Thermostat Replacement costs $139 on average. Following is a breakdown of the labor and parts estimates.

YourMechanic Price
$127 to $155
Labor: $77 -$96
Parts: $50 -$59
Average Dealer price
$203 to 230
Average Shop price
$154 to 174
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Our mechanics come to you ・Backed by 12-month, 12,000-mile guarantee・Fair and transparent pricing
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CarServiceEstimateShop/Dealer Price
1999 Mercedes-Benz S420V8-4.2LService typeCar Thermostat ReplacementEstimate$202.46Shop/Dealer Price$262.57 - $374.28
1998 Mercedes-Benz S420V8-4.2LService typeCar Thermostat ReplacementEstimate$202.46Shop/Dealer Price$262.71 - $374.53
1996 Mercedes-Benz S420V8-4.2LService typeCar Thermostat ReplacementEstimate$202.46Shop/Dealer Price$262.62 - $374.37
1997 Mercedes-Benz S420V8-4.2LService typeCar Thermostat ReplacementEstimate$202.46Shop/Dealer Price$262.66 - $374.45
1994 Mercedes-Benz S420V8-4.2LService typeCar Thermostat ReplacementEstimate$177.14Shop/Dealer Price$230.15 - $326.23
1995 Mercedes-Benz S420V8-4.2LService typeCar Thermostat ReplacementEstimate$184.14Shop/Dealer Price$239.66 - $337.62
Show example Mercedes-Benz S420 Car Thermostat Replacement prices

Car Thermostat Replacement Service & Cost

What is the Thermostat all about?

A thermostat is part of the cooling system that regulates the temperature of the coolant in the engine. The thermostat is a metal valve that has a temperature sensor built in. It can either be open or closed. When the thermostat is closed, it keeps the coolant in the engine. When the engine gets to a predetermined temperature, the thermostat opens allowing coolant to circulate. The circulation of coolant prevents the engine from overheating. If the thermostat fails to open, the car will overheat. If the thermostat fails to close, the engine may never reach the optimal temperature (~220F). The thermostat opens and closes many times when the car engine is running. It is the most common component in the cooling system to fail, causing the car to overheat.

Thermostat

Keep in mind:

  • The entire cooling system should be inspected when the thermostat is replaced.
  • When the thermostat is replaced, the gaskets and housings should be cleaned thoroughly.

How it's done:

  • Scan the computer in the car for codes.
  • Verify that the car is overheating.
  • Remove and replace thermostat if it is faulty.
  • Clean old gasket surfaces.
  • Remove corrosion from housings/hose connections.
  • Fill cooling system.
  • Check for leaks and proper operating temperatures.

Our recommendation:

Have the thermostat replaced anytime you have major work done on the coolant system.

What common symptoms indicate you may need to replace the Thermostat?

  • Engine overheats.
  • Car heater does not work.
  • Check Engine light is on.

How important is this service?

A vehicle’s engine gets extremely hot, and in order to avoid overheating, it needs to be properly cooled. The engine is cooled by a viscous liquid called coolant. The coolant is circulated around the engine, where it absorbs heat, which allows the engine to remain at a safe temperature. A fan then lowers the temperature of the coolant, which allows it to run back through the engine once more. The thermostat is responsible for determining when the coolant needs to enter the engine. The thermostat determines the temperature of the engine, and then acts as a valve that allows coolant in, or keeps coolant out. When the engine is too cold, the thermostat keeps coolant out; when the engine is too hot, it lets coolant in.

When the thermostat stops working, it will either get stuck open or closed. If the thermostat is stuck open, the coolant will constantly flow through the engine, absorbing too much heat, and the engine will never reach optimal running temperature. If the thermostat is stuck closed, the coolant will never circulate through the engine, and your engine will quickly overheat, which can cause severe damage.

Fast and easy Car Thermostat Replacement service at your home or office.

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Meet some of our expert Mercedes-Benz mechanics

Real customer reviews from Mercedes-Benz owners like you.

Chris

18 years of experience
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Chris
18 years of experience
fixed everything right up. i didn't have to wait long, as he came right on time.
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Chris

16 years of experience
169 reviews
Chris
16 years of experience
Chris is friendly and very professional. He communicates well and kept me in the loop from estimated arrival time to service progress to developing an estimate for additional work needed. I found Chris to be forthright and of high integrity. I appreciate his use of technology to communicate and show recommendations for future service work. I will gladly recommend Chirs to my friends and co-workers.
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Joseph

14 years of experience
108 reviews
Joseph
14 years of experience
Joseph is an extremely knowledgeable and professional mechanic. He is very detailed and thorough in his process and execution. He demonstrated this in his diagnosis and confirmation of the root cause to which the repair was intended to correct. Joe follows a process and set of best practices that should be a model for all mechanics. I very highly recommend Joe for his integrity and thoroughness with which he performs his job.
2007 MERCEDES-BENZ SLK350 - BRAKE PADS REPLACEMENT (FRONT, REAR) - NOTTINGHAM, MARYLAND

Chris

12 years of experience
87 reviews
Chris
12 years of experience
Fantastic mechanic. He arrived early and I was running behind but he patiently waited for me and changed out my brake pads on my Mercedes, explained other services he recommended and even explained and showed me my old brake pads. I will personally request him next time.
2011 MERCEDES-BENZ E350 - BRAKE PADS REPLACEMENT (FRONT) - CHULA VISTA, CALIFORNIA
Get an instant quote for your car
Our mechanics come to you ・Backed by 12-month, 12,000-mile guarantee・Fair and transparent pricing
Get a quote
CarServiceEstimateShop/Dealer Price
1999 Mercedes-Benz S420V8-4.2LService typeCar Thermostat ReplacementEstimate$202.46Shop/Dealer Price$262.57 - $374.28
1998 Mercedes-Benz S420V8-4.2LService typeCar Thermostat ReplacementEstimate$202.46Shop/Dealer Price$262.71 - $374.53
1996 Mercedes-Benz S420V8-4.2LService typeCar Thermostat ReplacementEstimate$202.46Shop/Dealer Price$262.62 - $374.37
1997 Mercedes-Benz S420V8-4.2LService typeCar Thermostat ReplacementEstimate$202.46Shop/Dealer Price$262.66 - $374.45
1994 Mercedes-Benz S420V8-4.2LService typeCar Thermostat ReplacementEstimate$177.14Shop/Dealer Price$230.15 - $326.23
1995 Mercedes-Benz S420V8-4.2LService typeCar Thermostat ReplacementEstimate$184.14Shop/Dealer Price$239.66 - $337.62
Show example Mercedes-Benz S420 Car Thermostat Replacement prices

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