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Service, Repairs & MOT

Automatic transmission replacement for your Mercedes

Book a local RAC Approved Garage that you can trust.

  • 12-months parts guarantee
  • Honest pricing
  • Exceptional customer service

Why choose the RAC for an automatic transmission fluid top-up?

At the RAC, we've got over 125 years' experience helping UK drivers. We have the skills and knowledge to keep your vehicle running. We'll give you results you can rely on at a price you can afford.

Automatic Transmission Fluid Change for Mercedes vehicles requires specialist tools and workshop facilities, so this work is completed through the RAC Approved Garage Network. Our approved garages service models such as A-Class, C-Class, GLC, E-Class, and EQA, following manufacturer procedures, certified equipment standards and rigorous quality checks. You receive transparent pricing, progress updates and RAC‑backed guarantees.

Close up of an RAC Mobile Mechanic underneath a car
A mechanic standing inside a garage

Book an automatic transmission fluid replacement

To help make sure you’re getting smooth gear shifts and a long transmission life you need to maintain your automatic transmission fluid. So when you need to, make sure you have that old fluid drained and refilled at an RAC Approved Garage.

Any work done will meet the high standards set by the RAC.
We’re friendly, straightforward and jargon-free
A mechanic inspecting the underside of a vehicle.

Book a diagnostic

A mechanic will check your car for faults and talk you through any repairs you might need. There are various ways to check for faults, which could include a physical examination or plugging in to check your car’s onboard engine management system.

We’ll look for any mechanical or electrical problems. If we need to, we’ll also check your car’s onboard engine management system. Depending on your car and issue, this will usually include: – Engine – Power steering – Brakes – Transmission – Exhaust system – Fuel injection system – Cooling system and air flow – Sensors

And it’s not just automatic transmission fluid replacements that we can do for your Mercedes

RAC Approved Garages offer MOTs and services. Our professional mechanics have the expertise and experience to make sure your vehicle is operating safely and efficiently – results you can rely on at a price you can afford.

A close up of an RAC mobile mechanic looking under the hood of a car

Try one of our RAC Approved Garages

Sahibs Auto Electric

4.0/5

We are London's go to centre for MOT, Servicing, Alternators, Starter Motors and Car Diagnostics. We pride ourselves in Car Electrics and are well renowned for are specialists in Car Alternators and Car Starter Motors. Established in 1980, we have nearly 40 years of trusted experience the industry.
3 Norbreck Parade, London, NW107HR

Gladstone tyres & autocare

4.3/5

Gladstone Garage is a family run business located in York that offers a range of MOT, car servicing, garage services and quality tyres including mobile tyre fitting for cars and vans in York. The technicians at Gladstone tyres & autocare have over 75 Years of experience and are happy to help you out whether you require welding or a simple bulb replacing. We pride ourselves on customer satisfaction and quality services. That's why we should be your first choice for a local garage in York for tyres, MOT, servicing and repairs. Please get in contact to see how we can help!!
Unit 1B, Outgang Lane, York, YO195UP

Moorhouse Garage Ltd

5.0/5

Hi, Here we have a higher duty of care as our technicians are main dealer trained including BMW and Mini, VAG Group (Volkswagen, Audi, Seat, Skoda and Bentley) and the FCA Family (Fiat, Chrysler, Jeep and Alfa Romeo) We also have main dealer level diagnostic tools for the above brands and extremely confident we can fix your vehicle for you. **Here at Moorhouse Garage we Are Able To Carry Out All Your Motoring Needs from a simple service to the depths of building a forged engine for you as we're a tuning and remapping centre too**. We Also Specialise in Dpf Cleaning Family Run Business for over 25 Years We hope that this is of interest and we would be very happy to answer any questions you have. We look forward to hearing from you. Kindest regards, Moorhouse Garage
Unit J, Moorhouse Park, Westerham, TN162ET

IN'n'OUT Autocentres Bracknell

4.2/5

At IN’n’OUT Autocentres we offer fixed prices MOTs and Servicing for any make and model of car with no hidden extras. We are proud to be a ‘Which? Trusted Trader’ so we are really a garage you can trust. We also have a 5 Star Trustpilot reviews rating. We provide OEM parts and 12 months warranty on all parts and servicing. We only use premium Castrol oils in all servicing. Our services are all completed ‘while-u-wait’ so you have never have the inconvenience of losing your car for the day. You can watch your car as it is being worked on through the viewing window or sit back and relax in our clean and comfortable customer lounges with FREE Wi-Fi and coffee and read the latest magazines. Check out our latest reviews and BOOK NOW!!
Unit 5B Western Trade Centre, Western Rd, Bracknell, RG121RW

Kmita Motors

4.0/5

We are a family run business providing excellent service to our customers. Our fully qualified and trained mechanics can offer all types of service repairs and diagnostic for any make of vehicle. We offer great service at affordable cost. Our mechanics hold a combined experience of motor vehicle repairs for over twenty years. They are fully trained and qualified, holding level 3 in motor vehicle repairs and obtaining a M.O. T Manager inspector certificate award.
85A Springhead Road, Northfleet, Gravesend, DA119QZ

Frequently asked questions about automatic transmission fluid change

Automatic transmission fluid should be changed every 30,000 to 60,000 miles. However, always check your vehicle’s manual for the manufacturer’s recommendation. Your driving habits and the conditions you drive in will affect how quickly your fluid degrades. Regular checks and following the manufacturer’s guidelines will help to make sure your transmission stays in good condition.

Some people believe that changing old transmission fluid can cause issues, especially in high-mileage vehicles. This myth stems from the fact that when automatic transmission fluid is changed, the new fluid can sometimes dislodge debris, causing problems. However, this is usually due to debris build-up.

If you don’t change the automatic transmission fluid, it can become contaminated and lose its effectiveness, leading to transmission wear and potential failure. Over time, dirty automatic transmission fluid can cause increased friction, overheating, and significant transmission damage. Regular changes will help you avoid costly repairs and keep the transmission running smoothly.

Fresh automatic transmission fluid is bright red and clear. If your fluid looks clean and smells fresh, it’s been changed recently. You can also check the service records for confirmation. If in doubt, ask your mechanic to check.

Signs that you might need a transmission flush include:

  • Slipping gears: The transmission struggles to stay in gear.
  • Delayed gear engagement: There’s a noticeable delay when shifting gears.
  • Overheating: The transmission becomes excessively hot.
  • Unusual noises: Grinding or whining sounds from the transmission.
  • Dirty fluid: The automatic transmission fluid is dark or discoloured.

A flush can help remove contaminants and restore the fluid’s effectiveness.

It’s often best to have a professional do it. The process can be messy and requires proper disposal of old fluid. Professional services also include checks and diagnostics to ensure everything is working.

Transmission fluid is used in automatic transmissions, while gearbox oil is used in manual transmissions. They’re made to do different jobs, so they’re not interchangeable. Automatic transmission fluid is designed for the hydraulic and cooling needs of automatic transmissions, while gearbox oil provides the necessary lubrication for manual transmissions.

An automatic transmission flush is a service where all the old automatic transmission fluid is removed, and new fluid is added. It helps remove contaminants and old fluid that might be stuck in the transmission. It’s more thorough than a simple fluid change and can help restore the transmission’s performance.

Yes, changing the automatic transmission fluid is necessary to keep your vehicle’s transmission running well. Over time, the fluid degrades and becomes less effective, leading to potential transmission problems. Regular changes help the transmission run smoothly and can prevent costly repairs down the line.

To extend the life of your automatic transmission fluid:

  • Regular maintenance: Follow the manufacturer’s guidelines for fluid changes.
  • Avoid excessive heat: Don’t overload your vehicle or tow heavy loads when you don’t have to.
  • Check for leaks: Regularly inspect your vehicle for fluid leaks.
  • Smooth driving: Avoid aggressive driving habits that can overheat the transmission.

Proper care and regular upkeep can significantly extend the life of your automatic transmission fluid and transmission.

An automatic transmission fluid change will typically take about 1 to 2 hours, depending on the vehicle and the service provider. This includes draining the old fluid, replacing the filter (if necessary), and refilling with new fluid. If more services or diagnostics are needed, it could take longer.

If your transmission fluid is low:

  • Check for leaks: Look for any visible leaks under the car.
  • Top up the fluid: Use the right type of fluid for your vehicle.
  • Monitor the fluid level: Regularly check the fluid level to make sure it stays within the recommended range.
  • Consult a mechanic: If the fluid level continues to drop speak to a mechanic so that they can inspect and fix any issues.