| Summary | |||
|---|---|---|---|
| Year: | 2003change | ||
| Make: | Mercurychange | ||
| Model: | Mountaineerchange | ||
| Sub Models: | Basechange | ||
| Engine Sizes: | 4.0L V6 FLEX, 4.6L V8 GASchange | ||
| Item: | Transmission Assembly | ||
| Condition: | OEM Used | ||
| Items Available: | 11 | ||
| Price Range: | $1,189 - $1,691 (before local discount) | ||
| Local Discount: | Up to $100.00 | ||
| Returns: |
Cancellation & Return Policy | ||
| Item: | Transmission Assembly change |
| Condition: | OEM Usedchange |
| Items Available: | 11 |
| Price Range: | $1,189 - $1,691 (before local discount) |
| Local Discount: | Up to $100.00 |
Quality Tested Parts
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1-year warranty
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30-Day Free ReturnsSelect the right Transmission for your 2003 Mercury Mountaineer
This part may have multiple fitment options depending on your vehicle's engine, drivetrain, and configuration. To ensure proper compatibility, please select the correct fitment below. If you’re unsure, we strongly recommend checking your VIN or vehicle build details before ordering. You can update or change the fitment selection at any time.
Transmission - Automatic Transmission (5R55S) 6 cylinder (4.0L) 4x2
Select FitmentThis fitment option is for 2003 Mercury Mountaineer 4x2. This is an automatic transmission. Select this option if your vehicle has a 4.0L engine. Verify the transmission model code is 5R55S before ordering.
Items in stock: 2
Items in stock: 2
Transmission - Automatic Transmission (5R55S) 6 cylinder (4.0L) 4x4
Select FitmentThis fitment option is for 2003 Mercury Mountaineer 4x4. This is an automatic transmission. Select this option if your vehicle has a 4.0L engine. It is made for 4WD models. Verify the transmission model code is 5R55S before ordering.
Items in stock: 8
Items in stock: 8
Transmission - Automatic Transmission (5R55S) 8 cylinder (4.6L) 4x2
Select FitmentThis fitment option is for 2003 Mercury Mountaineer 4x2. This is an automatic transmission. Select this option if your vehicle has a 4.6L engine. Verify the transmission model code is 5R55S before ordering.
Items in stock: 1
Items in stock: 1
Transmission - Automatic Transmission (5R55S) 8 cylinder (4.6L) 4x4
Select FitmentThis fitment option is for 2003 Mercury Mountaineer 4x4. This is an automatic transmission. Select this option if your vehicle has a 4.6L engine. It is made for 4WD models. Verify the transmission model code is 5R55S before ordering.
Items in stock: 0
Items in stock: 0
Interchange Fitment FAQs
A: All Transmission options shown on this page are matched to your selected configuration:
2003 Mercury Mountaineer.
Used OEM parts are dismantled from donor vehicles as complete assemblies, and a specific interchange fitment is assigned during this process.
Every detail shown in the fitment notes must match your vehicle exactly.
A: An interchange fitment option defines the exact donor vehicle configuration your part came from. For 2003 Mercury Mountaineer, this may include engine size, VIN code,
transmission model, drivetrain, axle ratio, and other critical identifiers. This data comes from VIN decoding, OEM information, and
physical inspection of the donor vehicle.
A: Used OEM parts are not universal. If any fitment detail for your 2003 Mercury Mountaineer differs from what is shown in the fitment notes,
the Transmission may not install, communicate with your vehicle, or function correctly. Always verify all fitment details before ordering.
A: Fitment information is captured when the donor vehicle is dismantled.
The yard decodes the VIN for 2003 Mercury Mountaineer, checks OEM data and interchange databases,
and verifies details during physical inspection. The resulting fitment is then assigned to the Transmission assembly.
A: Many 2003 Mercury Mountaineer vehicles were built with multiple configurations in the same year and trim. Trim name alone (XLT, Limited, Sport, etc.) is not enough.
You must match the exact configuration shown in the fitment notes—such as engine size, transmission type, drivetrain, and axle ratio—before selecting a Transmission.
A: You can find the VIN for your 2003 Mercury Mountaineer on
the driver-side dashboard (visible through the windshield), inside the driver-side door jamb, and on your registration or insurance documents.
The VIN helps confirm the correct configuration and fitment.
A: For transmission fitment, match transmission type (automatic or manual), number of speeds, drivetrain (2WD, 4WD, or AWD), and transmission model as shown in the fitment notes for
your 2003 Mercury Mountaineer.
All of these must match before you select a transmission.
A: 2WD, 4WD, and AWD transmissions are not interchangeable even if they look similar. The interchange fitment is assigned to the transmission based on the donor vehicle’s drivetrain,
so your 2003 Mercury Mountaineer must have the same drivetrain for the transmission to fit correctly.
Enter your Zip Code below to find parts near you. The more local you shop, the more you save off the original sale price!
Attention!
There are 4 Transmission Assembly choices for the
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Available Parts
- Engine Assembly (12)
- Transmission Assembly (11)
- A/C Control (9)
- Air Flow Meter/Sensor (5)
- Alternator (45)
- Chassis Computer (15)
- Combination Switch (-)
- Convertible Top Lift (-)
- Convertible Top Motor (-)
- DC Converter (Electric Car) (-)
- Distributor (-)
- Electric Door Motor (-)
- Engine Computer/Control Unit (3)
- Fuse Box (404)
- Headlight/Headlamp Motor (-)
- Heater Motor (8)
- Ignition Coil (-)
- Ignition Switch W/Key (129)
- Power Window Motor (2)
- Power Window Switch (-)
- Quarter Window Motor (-)
- Starter (53)
- Sun Roof Motor (-)
- Tailgate Lift Motor (-)
- Tailgate Motor (-)
- Windshield Washer Motor (-)
- Wiper Motor, Front (4)
- Wiper Motor, Rear (4)
- Wiper Transmission (-)
- A Pillar (3)
- Back Window (1)
- Bed Rail (-)
- Bumper Assembly, Front (-)
- Bumper Assembly, Rear (-)
- Bumper Bar, Front (1)
- Bumper Bar, Rear (4)
- Bumper Cover, Front (-)
- Bumper Cover, Rear (-)
- Cab Corner (-)
- Door Assembly, Back (-)
- Door Assembly, Front (4)
- Door Assembly, Rear (7)
- Door Handle, Rear (-)
- Door Latch, Rear (-)
- Door Mirror, Side (4)
- Door Trim Panel, Front (5)
- Door Vent Glass, Front (-)
- Door Window, Front (4)
- Door Window, Rear (2)
- Fender (2)
- Front Clip (-)
- Fuel Tank (-)
- Grille (2)
- Ground Effects (-)
- Header Panel (-)
- Headlight/Headlamp Door (-)
- Hood (1)
- Pillar (5)
- Quarter Panel (5)
- Quarter Window (9)
- Quarter Window Regulator, Rear (-)
- Radiator Support (1)
- Rear Clip Assembly (-)
- Rear Fender Assembly (-)
- Rear Trim Panel (5)
- Rear Vent Window (2)
- Roof (3)
- Roof Glass (-)
- Running Board (1)
- Tail Finish Panel (-)
- Tail Panel (-)
- Tailgate Assembly (-)
- Tires (-)
- Tires, Set (-)
- Tonneau Cover (-)
- Truck Bed (-)
- Truck Cab (-)
- Trunk Lid Pull Down (-)
- Valance, Front (-)
- Wheel Cover (-)
- Wheel Rim (60)
- Windshield Glass (-)
- Air Bag (10)
- Armrest (-)
- Cargo Cover (-)
- Console (9)
- Cruise Control Servo (-)
- Dash Assembly (-)
- Dash Panel (4)
- Gas Pedal (-)
- Glove Box (2)
- GPS / Info Screen (1)
- Head Up Display (-)
- Headrest (-)
- Inside Door Handle (-)
- Instrument Cluster (-)
- Interior, Complete (-)
- Jack Assembly (4)
- Night Vision Camera (-)
- Overhead Console (-)
- Radio / CD Player (102)
- Rear View Mirror (3)
- Roof Rack (2)
- Seat Track, Front (-)
- Seat, Front (34)
- Seat, Rear (-)
- Seat, Third Row (6)
- Seatbelt (12)
- Shift Lever (-)
- Speedometer (5)
- Steering Wheel (1)
- Sun Visor (134)
- Trailer Hitch (-)
- ABS Control Module/Pump (31)
- Air Injection Pump (-)
- Air Spring (-)
- Axle Carrier, Rear (129)
- Axle Housing (-)
- Axle Shaft (10)
- Axle, Front (-)
- Axle, Rear (-)
- Back Axle (-)
- Brake Master Cylinder (5)
- Bumper Shock (-)
- Cab Clip (-)
- Camshaft (-)
- Cylinder Head (-)
- Differential Assembly, Rear (-)
- Drive Shaft, Front (1)
- Drive Shaft, Rear (365)
- Engine Oil Cooler (-)
- Engine Pullout (-)
- Exhaust Manifold (-)
- Flywheel (25)
- Frame (15)
- Fuel Pump (-)
- Harmonic Balancer (-)
- Hub Bearing (-)
- I Beam (-)
- Intake Manifold (-)
- Leaf Spring, Front (-)
- Leaf Spring, Rear (-)
- Lower Control Arm, Front (-)
- Lower Control Arm, Rear (-)
- Muffler (-)
- Oil Pan (-)
- Power Brake Booster (5)
- Power Steering Pump (47)
- Radiator Overflow Bottle (5)
- Ring Gear And Pinion (-)
- Shock Absorber (-)
- Shock, Front (4)
- Shock, Rear (5)
- Spindle (-)
- Spoiler, Rear (-)
- Steering Column (-)
- Steering Gear (1)
- Strut (-)
- Stub Axle, Rear (-)
- Suspension Compressor (-)
- Suspension Cross Member (-)
- Throttle Body (23)
- Timing Cover (-)
- Torque Converter (-)
- Torsion Bar (-)
- Transfer Case Assembly (2)
- Transfer Case Motor (-)
- Transmission Cooler (2)
- Turbo (-)
- Upper Control Arm, Front (-)
- Upper Control Arm, Rear (-)
- Vacuum Pump (-)
- Valve Cover (-)
- Water Pump (-)
- Window Regulator, Front (3)
- Window Regulator, Rear (2)
