Hello all,
I have a few questions regarding the 2002/2003 Ford Explorer/Mercury Mountaineer engine swap. Please let me know if you see any information in this post that is incorrect, and I will update this post accordingly. I want to compile all of the information I have found first and then I will post follow-up questions afterwards.
After doing my research I found that the 2002 and 2003 model years of the Ford Explorer are the easiest 4.6 2v PI Explorer motors to swap into a 1994/1995 Thunderbird because they do not use an electronic throttle body while the 2004/2005 model years of the Explorer do which makes them less desirable when swapping them into a Thunderbird. The main benefit of using the Explorer motor over swapping in a 1999-2004 Mustang GT motor is that the Explorer engine blocks are made of aluminum while the Mustang GT engine blocks are made of steel. On average, it sounds like the Explorer motor is about 80 lbs. lighter than the Mustang engine which improves handling and acceleration due to weight reduction of the front end. Performance wise, the Explorer and Mustang GT PI engines seem to be identical. I read on other posts that the reason the Mustang GT was rated for a higher horsepower from the factory was because it had a more aggressive tune and a true dual exhaust system that was less restrictive compared to the Explorer.
In order to complete the swap to a 2002/2003 Explorer PI motor, there are a few modifications needed to get everything to hook up correctly to a 1994/1995 Thunderbird.
This is a list of the parts needed from a 1996/1997 Thunderbird:
The rest of the parts can be reused or replaced off the 1994/1995 Thunderbird 4.6 2v SOHC Non-PI engine:
There are a few parts that require further discussion to identify some of the difficulties and nuances of this engine swap.
Intake Manifold
There seems to be a few different discussions on the coolant port and temperature sensor location for the Explorer and Mustang GT intake manifold. The main difference between the PI intake and the non-PI intake when adapting it to a Thunderbird is that the Thunderbird has 2 temperature sensors. This creates an issue because both the Mustang GT and the Explorer intake manifold only have one location for a temperature sensor. Some people have tried to use a T-fitting to use both of the sensors but this method gives a false reading to the temperature gauge on the dashboard. The solution to this problem is to drill a hole on the rear driver's side of the intake manifold to be able to use the 2nd EEC temperature sensor on the Thunderbird. On some of the intake manifolds for the Explorer and the Mustang GT there is a pipe nipple on the aluminum crossover that can be drilled and tapped to fit this 2nd temperature sensor, but it is not clear which model years featured this updated design.
Exhaust Manifold
The existing exhaust manifolds from the 1994/1995 Thunderbird will work with the 2002/2003 Explorer/Mountaineer motor.
Oil Pan
The 2002/2003 Explorer/Mountaineer and the 1999 – 2004 Mustang GT oil pan will not fit with the 1994/1995 Thunderbird K-Member. Since the oil pan interferes it is necessary to use a 1994/1995 Thunderbird oil pan.
Also, the oil pickup tube needs to match the style of the oil pan. Therefore, you should use the existing 1994/1995 Thunderbird oil pickup tube in combination with the pan. The MN12 k-member is designed in such a way that only the oil pan and pickup from the Thunderbird will work. It is the only one that will clear the k-member, and the MN12 pickup tube is the only one that works with the MN12 oil pan.
Fuel Lines
The 1994/1995 Thunderbird Fuel Lines meet the intake manifold where the Throttle Body is on the new 2002/2003 Explorer/Mountaineer Engine. Therefore, they do not line up properly with the new fuel rail. You can either bend them back or buy new fuel lines. The fuel lines go from the fuel rail to the fuel filter locater under the passenger side door. This is also a good time to change the fuel filter.
Motor Mounts
It is a good idea to replace the stock motor mounts for solid rubber ones. There are 2 versions that will work with the 2002/2003 Explorer/Mountaineer. The 5.0 Motor mounts or the 4.6 motor mounts. The 4.6 Motor Mounts will make the engine sit a little bit higher. The 5.0 Motor Mounts make the new engine sit closer to the stock height of the original engine. It is not necessary to replace the motor mounts to put the new engine in unless they are severely worn out. Depending on where the 2002/2003 Explorer/Mountaineer Block was manufactured, the motor mounts may need to be ground down in order to fit. The stock 4.6 2v that came in the Thunderbirds in 1994/1995 were made in the Romeo Plant. However, some of the 2002/2003 Explorer/Mountaineer 4.6 2v engines were made in the Windsor Pant. The engines that were produced in the Windsor plant have additional webbing that can interfere with the motor mounts on the 1994/1995 Thunderbird. If this is the case, then the motor mounts will need to be modified.
Torque Converter
While the engine is out of the car it is a good time to replace the torque converter with a better one. Either the Lincoln Mark VIII or the 2003 Mercury Marauder Torque converter will work. The stock Thunderbird torque converter has a stall speed of 2300 RPM while the stock Lincoln Mark VIII and Mustang GT torque converters have a stall speed of 2700 RPM. The Mercury Marauder and Mustang Mach 1 torque converters can also be used and have the highest stock stall speed at 2800 RPM.
Mercury Marauder Torque Converter P/N: F63HSHD
Flex Plate
The flex plate on the 2002/2003 Explorer/Mountaineer is for a different size bolt pattern torque converter than the torque converter on the stock 1994/1995 Thunderbird with a 4r70w transmission.
EEC Tuning
It is not required to tune the PCM to get the engine to start but is recommended. The car should be able to run and drive with a stock tune. However, drivability and performance will be gained by getting a custom tune.
Timing Covers
The 2002/2003 Explorer/Mountaineer front timing cover will not work because it changes the location of the power steering pump.
The 1996/1997 Thunderbird will not work with the 2002/2003 Explorer/Mountaineer because one of the timing cover bolts does not line up.
You will need a 1994/1995 Thunderbird 4.6 V8 front timing cover or any SOHC 4.6L v8 front timing cover made in 94/95 as long as the casting number on the top left start with "F3AE"
Therefore, it is necessary to use a 1994/1995 Thunderbird front timing cover with the 2002/2003 Explorer/Mountaineer engine. This timing cover will line up perfectly with the new motor and keep the power steering pump in the same location as the stock 1994/1995 engine.
Use a 2002/2003 Explorer serpentine belt with the 1994/1995 Timing Cover.
Gaskets
The following gaskets should be replaced.
1) Timing Cover Gaskets - There are 3 of these and should be replaced seeing how they can rip when swapping over easily.
2) Oil Pan Gasket - Remember to torque it down correctly.
3) Timing Cover Crank Seal - This is the rubber seal that’s in the timing cover that sits around the crankshaft sticking out in front of the block.
4) Oil Filter Adapter Gasket - The Oil filter and lower radiator hose are at a different angle on the 02+ explorer blocks so swap over your adapter.
5) Valve Cover Gaskets
6) Intake Manifold Gaskets
7) Torque Convertor Retaining nuts - Made of a soft metal and should be replaced when doing a motor swap.
Engine Harness Electrical Wiring
It is necessary to have the engine wiring harness for the new engine that you will be putting in the car. Some of the connector styles may be different which will require you to swap the existing connectors on the 1994/1995 engine harness with the new ones. All of the wires will transfer over however the wire colors may differ depending on the year. Use wiring schematics to make sure all of the wires are connected to the right location. Some of the pigtail connectors on the 1994/1995 Engine Harness may also need to be extended.
The 1996/1997 Thunderbird engine harness uses many of the same connectors and wire lengths as the 2002/2003 Explorer/Mountaineer. However, the 1996-1998 Thunderbird engine harness cannot be swapped into the 1994/1995 Thunderbird engine harness because the main plug connectors are different. Doing this swap would require changing the PCM to a 1996/1997 Thunderbird PCM.
If you use the thunderbird sensors, the only Explorer/Mountaineer connector you will need is the IAC. The rest of the thunderbird sensors can remain the same and still work with the Explorer/Mountaineer Engine. However, some of the wires that may need to be lengthen if the connector won’t reach the sensor.
IAC (Idle Air Control) Valve
Use the 1999-2002 IAC valve from the Explorer/Mountaineer engine and the associated connector from the Explorer/Mountaineer wiring harness. No lengthening is necessary, just swap the connectors.
Thunderbird white/blue and red
Explorer white/blue and purple/white
TPS (Throttle Position Sensor)
1994/1995 Thunderbird uses the same wires and connector as the 2002/2003 Explorer/Mountaineer, but the wires will need to be lengthened in most cases.
EGR (Exhaust Gas Recirculation) Flow Sensor
The 1994/1995 Thunderbird uses the same wire colors as the 2002/2003 Explorer/Mountaineer.
However, the connector for the EGR Flow sensor is specific to the 2002/2003 Explorer/Mountaineer. This connector will need to be removed from the Explorer/Mountaineer engine harness and spliced into the existing 1994/1995 Thunderbird Harness. No lengthening is necessary, just swap the connectors.
EGR (Exhaust Gas Recirculation) Vacuum Regulator
1994/1995 Thunderbird uses the same wires and connector as the 2002/2003 Explorer/Mountaineer, but the wires will need to be lengthened in most cases.
EEC (Electronic Engine Control) Engine Temp
Thunderbird green/red and grey/red
Explorer green/yellow and tan/red
I have a few questions regarding the 2002/2003 Ford Explorer/Mercury Mountaineer engine swap. Please let me know if you see any information in this post that is incorrect, and I will update this post accordingly. I want to compile all of the information I have found first and then I will post follow-up questions afterwards.
After doing my research I found that the 2002 and 2003 model years of the Ford Explorer are the easiest 4.6 2v PI Explorer motors to swap into a 1994/1995 Thunderbird because they do not use an electronic throttle body while the 2004/2005 model years of the Explorer do which makes them less desirable when swapping them into a Thunderbird. The main benefit of using the Explorer motor over swapping in a 1999-2004 Mustang GT motor is that the Explorer engine blocks are made of aluminum while the Mustang GT engine blocks are made of steel. On average, it sounds like the Explorer motor is about 80 lbs. lighter than the Mustang engine which improves handling and acceleration due to weight reduction of the front end. Performance wise, the Explorer and Mustang GT PI engines seem to be identical. I read on other posts that the reason the Mustang GT was rated for a higher horsepower from the factory was because it had a more aggressive tune and a true dual exhaust system that was less restrictive compared to the Explorer.
In order to complete the swap to a 2002/2003 Explorer PI motor, there are a few modifications needed to get everything to hook up correctly to a 1994/1995 Thunderbird.
This is a list of the parts needed from a 1996/1997 Thunderbird:
- Fuel Rail with a Fuel Pressure Regulator (FPR)
- Fuel Lines
- Throttle Cable
- Throttle Cable Bracket
- Alternator Bracket
The rest of the parts can be reused or replaced off the 1994/1995 Thunderbird 4.6 2v SOHC Non-PI engine:
- Front Timing Cover Gasket F1AZ-6020-A
- Front Timing Cover Gasket F1AZ-6020-B
- Front Timing Cover Gasket F1AZ-6020-C
- Front Crank Seal for in the Front Cover F5AZ-6700-A
- Oil Pan Gasket F4AZ-6710-A
- Oil Filter Adapter Gasket F6AZ-6840-BA
- Torque Convertor Nuts Pack of 4 378941-S441 or MM-169-H
- Valve Cover Gaskets F1AZ6584A, F1AZ6584B, F6AZ6584AA, F6AZ6584BA
- Exhaust Manifold Gasket YC2Z9448CA
- Thermostat Housing O-Ring F1VY8255A
- Fuel Injector O-Rings 19238128
- Oil Pickup Tube O-Ring
- Oxygen Sensors
- Timing Cover
- Valve Covers
- Harmonic Balancer
- Oil Pan
- Oil Pickup Tube
- Oil Dipstick
- Coil Packs
- Spark Plugs
- Spark Plug Wires
- Stock 19lb Fuel Injectors
- A/C Compressor
- Alternator
- Power Steering Pump
- Oil Filter Adapter
- Exhaust Manifolds
- Cruise Control Cable
There are a few parts that require further discussion to identify some of the difficulties and nuances of this engine swap.
Intake Manifold
There seems to be a few different discussions on the coolant port and temperature sensor location for the Explorer and Mustang GT intake manifold. The main difference between the PI intake and the non-PI intake when adapting it to a Thunderbird is that the Thunderbird has 2 temperature sensors. This creates an issue because both the Mustang GT and the Explorer intake manifold only have one location for a temperature sensor. Some people have tried to use a T-fitting to use both of the sensors but this method gives a false reading to the temperature gauge on the dashboard. The solution to this problem is to drill a hole on the rear driver's side of the intake manifold to be able to use the 2nd EEC temperature sensor on the Thunderbird. On some of the intake manifolds for the Explorer and the Mustang GT there is a pipe nipple on the aluminum crossover that can be drilled and tapped to fit this 2nd temperature sensor, but it is not clear which model years featured this updated design.
Exhaust Manifold
The existing exhaust manifolds from the 1994/1995 Thunderbird will work with the 2002/2003 Explorer/Mountaineer motor.
Oil Pan
The 2002/2003 Explorer/Mountaineer and the 1999 – 2004 Mustang GT oil pan will not fit with the 1994/1995 Thunderbird K-Member. Since the oil pan interferes it is necessary to use a 1994/1995 Thunderbird oil pan.
Also, the oil pickup tube needs to match the style of the oil pan. Therefore, you should use the existing 1994/1995 Thunderbird oil pickup tube in combination with the pan. The MN12 k-member is designed in such a way that only the oil pan and pickup from the Thunderbird will work. It is the only one that will clear the k-member, and the MN12 pickup tube is the only one that works with the MN12 oil pan.
Fuel Lines
The 1994/1995 Thunderbird Fuel Lines meet the intake manifold where the Throttle Body is on the new 2002/2003 Explorer/Mountaineer Engine. Therefore, they do not line up properly with the new fuel rail. You can either bend them back or buy new fuel lines. The fuel lines go from the fuel rail to the fuel filter locater under the passenger side door. This is also a good time to change the fuel filter.
Motor Mounts
It is a good idea to replace the stock motor mounts for solid rubber ones. There are 2 versions that will work with the 2002/2003 Explorer/Mountaineer. The 5.0 Motor mounts or the 4.6 motor mounts. The 4.6 Motor Mounts will make the engine sit a little bit higher. The 5.0 Motor Mounts make the new engine sit closer to the stock height of the original engine. It is not necessary to replace the motor mounts to put the new engine in unless they are severely worn out. Depending on where the 2002/2003 Explorer/Mountaineer Block was manufactured, the motor mounts may need to be ground down in order to fit. The stock 4.6 2v that came in the Thunderbirds in 1994/1995 were made in the Romeo Plant. However, some of the 2002/2003 Explorer/Mountaineer 4.6 2v engines were made in the Windsor Pant. The engines that were produced in the Windsor plant have additional webbing that can interfere with the motor mounts on the 1994/1995 Thunderbird. If this is the case, then the motor mounts will need to be modified.
Torque Converter
While the engine is out of the car it is a good time to replace the torque converter with a better one. Either the Lincoln Mark VIII or the 2003 Mercury Marauder Torque converter will work. The stock Thunderbird torque converter has a stall speed of 2300 RPM while the stock Lincoln Mark VIII and Mustang GT torque converters have a stall speed of 2700 RPM. The Mercury Marauder and Mustang Mach 1 torque converters can also be used and have the highest stock stall speed at 2800 RPM.
Mercury Marauder Torque Converter P/N: F63HSHD
Flex Plate
The flex plate on the 2002/2003 Explorer/Mountaineer is for a different size bolt pattern torque converter than the torque converter on the stock 1994/1995 Thunderbird with a 4r70w transmission.
EEC Tuning
It is not required to tune the PCM to get the engine to start but is recommended. The car should be able to run and drive with a stock tune. However, drivability and performance will be gained by getting a custom tune.
Timing Covers
The 2002/2003 Explorer/Mountaineer front timing cover will not work because it changes the location of the power steering pump.
The 1996/1997 Thunderbird will not work with the 2002/2003 Explorer/Mountaineer because one of the timing cover bolts does not line up.
You will need a 1994/1995 Thunderbird 4.6 V8 front timing cover or any SOHC 4.6L v8 front timing cover made in 94/95 as long as the casting number on the top left start with "F3AE"
Therefore, it is necessary to use a 1994/1995 Thunderbird front timing cover with the 2002/2003 Explorer/Mountaineer engine. This timing cover will line up perfectly with the new motor and keep the power steering pump in the same location as the stock 1994/1995 engine.
Use a 2002/2003 Explorer serpentine belt with the 1994/1995 Timing Cover.
Gaskets
The following gaskets should be replaced.
1) Timing Cover Gaskets - There are 3 of these and should be replaced seeing how they can rip when swapping over easily.
2) Oil Pan Gasket - Remember to torque it down correctly.
3) Timing Cover Crank Seal - This is the rubber seal that’s in the timing cover that sits around the crankshaft sticking out in front of the block.
4) Oil Filter Adapter Gasket - The Oil filter and lower radiator hose are at a different angle on the 02+ explorer blocks so swap over your adapter.
5) Valve Cover Gaskets
6) Intake Manifold Gaskets
7) Torque Convertor Retaining nuts - Made of a soft metal and should be replaced when doing a motor swap.
Engine Harness Electrical Wiring
It is necessary to have the engine wiring harness for the new engine that you will be putting in the car. Some of the connector styles may be different which will require you to swap the existing connectors on the 1994/1995 engine harness with the new ones. All of the wires will transfer over however the wire colors may differ depending on the year. Use wiring schematics to make sure all of the wires are connected to the right location. Some of the pigtail connectors on the 1994/1995 Engine Harness may also need to be extended.
The 1996/1997 Thunderbird engine harness uses many of the same connectors and wire lengths as the 2002/2003 Explorer/Mountaineer. However, the 1996-1998 Thunderbird engine harness cannot be swapped into the 1994/1995 Thunderbird engine harness because the main plug connectors are different. Doing this swap would require changing the PCM to a 1996/1997 Thunderbird PCM.
If you use the thunderbird sensors, the only Explorer/Mountaineer connector you will need is the IAC. The rest of the thunderbird sensors can remain the same and still work with the Explorer/Mountaineer Engine. However, some of the wires that may need to be lengthen if the connector won’t reach the sensor.
IAC (Idle Air Control) Valve
Use the 1999-2002 IAC valve from the Explorer/Mountaineer engine and the associated connector from the Explorer/Mountaineer wiring harness. No lengthening is necessary, just swap the connectors.
Thunderbird white/blue and red
Explorer white/blue and purple/white
TPS (Throttle Position Sensor)
1994/1995 Thunderbird uses the same wires and connector as the 2002/2003 Explorer/Mountaineer, but the wires will need to be lengthened in most cases.
EGR (Exhaust Gas Recirculation) Flow Sensor
The 1994/1995 Thunderbird uses the same wire colors as the 2002/2003 Explorer/Mountaineer.
However, the connector for the EGR Flow sensor is specific to the 2002/2003 Explorer/Mountaineer. This connector will need to be removed from the Explorer/Mountaineer engine harness and spliced into the existing 1994/1995 Thunderbird Harness. No lengthening is necessary, just swap the connectors.
EGR (Exhaust Gas Recirculation) Vacuum Regulator
1994/1995 Thunderbird uses the same wires and connector as the 2002/2003 Explorer/Mountaineer, but the wires will need to be lengthened in most cases.
EEC (Electronic Engine Control) Engine Temp
Thunderbird green/red and grey/red
Explorer green/yellow and tan/red
