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4.0L V6 to 4.6L V8 swap how-to - 2005-2010

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4.0L V6 to 4.6L V8 swap how-to - 2005-2010

Old 12-01-2018, 04:14 PM
Join Date: Mar 2018
Location: New York
Posts: 14

Originally Posted by JimC View Post
You need a tune that disables the PATS, the anti-theft system doesn't recognize your key because it is programmed to the old ECM. That's why it cranks but won't start.
i have a complete donor car, if swap the PATS parts into my car will it work to start it up with out a tune disabling the PATS?
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Old 12-02-2018, 07:29 AM
Join Date: Mar 2018
Location: New York
Posts: 14
Default pcm and harness question

i have a complete 2006 4.6 donor car, my current car is a 2007 4.0.

My question is will i run into any issues using the 2006 pcm/harness in my 2007

If so what might i expect?
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Old 12-02-2018, 09:52 AM
JimC's Avatar
Join Date: May 2006
Location: North Carolina
Posts: 7,303

I've never done the swap myself, but several friends did. As far as I know every one of them had to do a PATS disable tune even though they had the donor car.
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Old 03-10-2019, 07:36 PM
Benito Mendoza Jr.
Join Date: Mar 2019
Location: nevada
Posts: 1
Default 2005 v6 automatic -swapping to 2009 4.6 with manual trans

Originally Posted by tx_zstang View Post
Next, get your new power plant in the car.

Before Installing the V8

With the engine out, you'll want to do a few things NOW.

1. Remove the V6 fuel line from the side steel line. Use a fuel line disconnect tool.

2. Remove the v6 heater hoses from the firewall unless you plan to reuse them. This can be a challenge, as there are 2 large clips that the hose snaps into for easy installation, but pita removal. I use 2 small flat screwdrivers to pry the clip tabs down and pull the hose end out, then remove the clip once the hose is off.

3. Run/route the V8 a/c lines. Connect the longer one to where the v6 one was removed near the brake fluid reservoir. The hose to the condenser can be added later, but it's far easier to do it now as well. Use some of the green oil from the v6 lines to lube the o-rings on the replacement lines before installing them. Reinstall the retaining clip on the connector by the brake reservoir. Do not overtighten the bolt to the condenser. Secure the lines to the frame with zipties or with factory snap hold-down thingy.

4. Clean up any mess, touch up any paint, etc.

5. Install the V8 PCM, or you can do this later.

If you are contemplating doing a k-member swap, NOW is the perfect time to do it!

If you are changing (upgrading) motor mounts, replace them now.

Prepping the V8 and Transmission

I prefer to drop in the motor and transmission together as one unit, because it is far easier to connect them together and to run and connect the engine wiring harness when they are out of the car.

If they are already together, you can skip this part of the installation.

For an automatic, be sure the flexplate is installed on the motor.

Install the torque converter into the transmisison. Make sure it goes in 3 different 'clicks' or steps; rotate the converter between each click to get it all the way in. When installed properly, if you run a straight edge across the face of the bellhousing, the converter body or plate will be about 1" from the bellhousing front. The center '****' of the converter is slightly within the bellhousing, by maybe 1/4".

Attachment 47788

Carefully connect the transmission and engine together. They should go together easily. It can help to put a little grease on the guide dowel pins.
If using the stock torque converter with adapter or a torque converter with studs, make sure the converter studs go into the holes in the flexplate.

WARNING: DO NOT secure the torque converter to the flexplate until the transmission is FULLY SEATED against the engine! You'll pull the converter out of position and damage the transmission pump. Unfortunately, it has happened here.

Snug the trans to the motor. If using an automatic transmission, make sure there is a little space between the flexplate and converter front or front of the adatper plate; 1/8" is typical.

Attachment 47789

Install the 4 torque converter nuts or bolts to secure the converter to the flex plate. Use blue loctite on the nuts or bolts. I think I torqued them to 30 ft-lbs. When the converter is secured, rotate the engine at least one full revolution to make sure there is no binding. The compression of the motor will make it difficult at times.

Install the rubber seal plug back into the access hole on the engine (lower driver side).

Install all front accessories, including a/c and p/s, water pump pulley, and idler pulleys. I opt to install the alternator separately and lift the motor by the alternator bolts, while others lift by the heads. If you lift by the heads, you can install the alternator and belt ahead of time.

Install/connect the engine wiring harness, connecting all things you can, including any transmission connections.
Be careful at the back of the motor, as the IMRC plug and knock sensor plugs are the same, shaped round like for an O2 sensor. The plug with 3 wires goes to the knock sensors; the plug with 4 wires and one of them being red go to the IMRC motor (if you have delete plates, you wont have the IMRC and should tape-over the connector); you wont be able to connect the IMRC until after the motor is installed and the intake manifold is installed.

If not using headers, stock exhaust manifolds should be installed now if they are not already on the motor, using new gaskets

TIP: If you are going to be installing long-tube headers, do not install the headers until the motor and trans are in the car. This applies to American Racing Headers and possibly others.

Make sure the motor mount support brackets are attached to the engine, which they should be already anyways.

Note that the intake manifold and fuel rails must wait until the motor is installed.

Installing the V8

Now getting to the real fun. Lower the motor and transmission into the car. Use the reversed process as you used when removing the V6. Be careful of the transmission end so it does not drag on the ground or floor. Carefully and slowly guide the assembly into position. The oil pan may tend to hang/bind on the front of the K-member, so watch out for that.

Attachment 47790

Work the motor into place, onto the side mounts. Get the mounts onto the stock mount studs, or if using aftermarket mounts, get bolts into place, but do not tighten anything yet.

Center the engine on the motor mounts; watch out for this, because you can easily shift the motor too far to one side on the motor mounts. A large pry bar can help you get it centered, before the motor is fully resting on the mounts.

Get the transmission at roughly the proper height as well, FLIP OVER THE CROSSMEMBER, and install it to the car. Lower the transmission onto the mount and secure the mounting bolts.

Now install and tighten the motor mount nuts or bolts.

TIP: If using headers and aftermarket motor mounts, including an aftermarket K-member, you may need to reverse the orientation of the motor bolt on the passenger side. For my American Racing headers and BMR K-member, I had to run the bolt UP from the bottom and secure the nut from the top side, whereas on the driver side, the bolt was run down from the top with nut on the bottom.

Attachment 47791

If you will be installing long tube headers, install them now if you haven't already installed them. Sometimes it is easier to install the headers while the motor is still held by the chains/lift, in case you need to remove one of the motor mount brackets.

With the motor and trans sitting solidly in place, remove the chains and lift.

Connect the heater hoses to the steel heater lines at the back of the block, passenger side. Note that there is a "bolt from hell" on the back of the head that holds the coolant lines to the block (the lines run in the intake manifold valley). Install clamps on the hoses.

Connect the small ground strap from near the master cylinder to the back of the head, using a 10mm wrench.

Check to make sure, but there should already be a large ground on the passenger side, the battery cable ground to one of the motor mount bracket studs; make sure that's there.

Install the V8 pcm if not already done.

Connect the a/c lines to the compressor. Put a little of the green oil on the o-rings on the lines. Snap them into place, and install the safety retaining clips. (Tip: if using used lines, install new green o-rings on the lines first.)

Connect the power steering steel line to the steering shaft. Install the power steering reservoir hoses.

Install the radiator fan shroud, and reconnect the fan wiring plug.

Install the coolant crossover (if not already on the engine).

Install the alternator if not already installed.

Install the lower radiator T hose, connecting to bottom of radiator. For 05/06,
install the thermostat housing and hoses.
The hose that runs up to the degas bottle can be connected when the bottle is reinstalled later.

Connect the a/c pressure sensor connector to the a/c line, driver front near radiator.

Install the drive belt. Make sure it clears the radiator hose near the power steering pulley.

Connect the wiring harness to the PCM, plugging in the 2 connectors. Use the levers on the connectors to pull the connectors into their locked positions.

Connect the square or rectangular power connector to the engine harness.

Install the BEC connector to the bottom of the BEC. Position the connector to the bottom of the BEC, press gently into place, tighten part-way on the top retaining bolt, which will pull the connector part-way on, then from the bottom, push the connector into the bottom of the bec; you'll feel it snap into place all the way. Snug the top bolt to secure the connector.
(Note that if you only try to pull up the connector using the top bolt, it wont seat properly. It is a 2-step process to get it properly seated.)

Install the top radiator hose and degas bottle, connect the lower hose on the bottle to the T to the bottom hose or t-stat, and the top small hose on the bottle as it was on the V6.

Remove any tape on the intake ports. Clean the ports to remove any residue and oil. You want the ports clean and dry.
Attachment 47792

Connect the brake booster vacuum hose to the back of the intake manifold.
Install the intake manifold; check the gaskets on the manifold, make sure they are all there and they are clean; install new ones as needed.
Secure the manifold with 10 bolts; the one that is a stud goes on the driver side back corner. Torque them to 89 INCH-lbs (roughly 9 ft-lbs).

Install the fuel rails and injectors. Put some oil on the injector o-rings, push them into place into the intake manifold. Secure to the manifold with the original 4 studs, 2 on each side.

Connect the fuel line to the fuel rail; BE SURE TO INSTALL THE SAFETY CLIP, otherwise the line WILL pop out under pressure.
The other end of the fuel hose should already be connected to the fuel line at the fender, but if not, connect it there, too, by pushing it solidly onto the line.

Install the COPs onto the spark plugs. Secure each with its bolt, snugged down (torque spec is 89 inch pounds).

Connect wiring harness connectors to the fuel injectors and COPs.

Connect Fuel Rail Pressure Sensor connector.
Connect vacuum line from fuel pressure connector to T in brake hose line.

Connect wiring harness connectors to throttle body (both sides). Push in the red retainers to lock into place. (If throttle body is not attached to intake manifold, install it and connect the wires.)

Connect driver-side valve cover hose to lower-front intake manifold port. NOTE: AN INLINE FILTER SHOULD BE USED HERE TO KEEP OIL OUT OF THE ENGINE. That can be added later as needed.

Connect evap vacuum line to top front driver side port of intake manifold.

Install intake air pipe and filter.
Connect passenger-side valve cover vent to intake pipe.
Attachment 47793

Now move to under the car. Connect shifter (manual trans) or shift cable (automatic trans). Install auto trans cooling lines, using 2 wrenches on the retaining nuts.

Connect driveshaft; use loctite on the bolts.

Install exhaust. Install and connect O2 sensors, especially the front ones.

Fill car with coolant.
Fill/replace power steering fluid.
For manual trans, full brake reservoir and prime/bleed the clutch (you can slowly press/release the pedal up to 100 times to build pressure); top off the brake fluid often.
For auto trans, add initial fluid (you'll need to add more fluid before driving once engine warms up).

Evacuate and charge the a/c system. Hint: if you have the vaccum pump, hook it up before now to have it drawing down the system so that by now, you can simply add the freon and oil.

Lastly, connect the battery, positive post first of course.

Load your startup tune. Crank it up!
doin the swap and I have a donar car is it plug and play if I take every thing from the engine compartment and transfer to mine harness Ecu and every thing
Benito Mendoza Jr. is offline  
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