V8 Explorer Swap -> Wiring Questions

[gfennie77]

Hey guys,

Here's a few questions for the "V8 Veterans" (preferably of a 1993 Mustang GT 5.0 swap).

Scenario:

1991 Ford Explorer
1993 Ford Mustang GT Engine, Computer, & Wiring
Ford C4 Transmission
Dana 20 Transfer Case

Next Steps:

1) Splice "Explorer" harness -> "Mustang" harness
2) Connect vaccuum lines
3) Install tranny & transfer case

(The engine has already been 'dropped' in.)

Questions:

1) The "Ford MotorSport 5.0 Main Harness Installation Guide" tells me that there are two 'connectors' on the 5.0 "Main" harness that have to be 'cut' in order to splice these wires to their appropriate location on the Explorer "Chassis" harness. A BROWN 8-pin connector (near the MAS Air Sensor), and a GREEN 8 pin connector (near the EEC-IV Computer.

(A) Does anybody have a wiring diagram that they could send me?
(B) The documentation is not too helpful - and the Haynes manuals are useless. I have ordered a few HELMS manuals to assist in the process.
(C) Where EXACTLY should I splice all these wires:?
(c1) Crank Only
(c2) Crank & Run
(c3) Oil Pressure Indicator (Dash)
(c4) Engine Coolant Temp Indicator (Dash)

(Color combinations would be extremely helpful). :>)


2) 5.0 Sensor Mounting: Where (and how) is the best way to mount the TAD and TAB sensors. Passenger fenderwall?

Thanks!
Graham

 

[Guy Groves]

Here it is in detail.....

You can "splice" the harness or build an intermediate harness to integrate the two. If you "splice" all you are really doing is moving wires from one connector to another. I would not recomend actual splices. If the harnesses are not isolated through a connector you could have maintenance headaches in the future (the harnesses won't come apart).

There are about 14 circuts to integrate the main engine harness to the body harness. There are also some extra circuts that you will want to re-route. For example my rear defrost circut was removed with the original V6 engine harness. Thus it was required for me to run a lead between two body harness connectors to maintain the circut. I also ran the power leads (fused links) of the main engine harness through the Explorer power distribution / fuse block instead of connecting them to the battery.

In total there are about 22 circuts to trace down and deal with. Also make sure your GROUND connections are good and located properly or it won't work.

When I did my conversion I moved my battery to the driver side. I also moved my main distribution block and starter relay as well. I did this to gain room for my air intake and to locate my compressor on the passenger side. I also built intermediate harnesses to integrate everything.

I have a pdf file of intermediate harnesses I built to integrate my 92 explorer with the FMS Hot rod (91-93 mustang) harness.
E-mail me at guygroves@earthlink.net I I will dig them up and send them.

Try the local library for wire harness diagrams.


NOTE: The brown 8-pin connector you mention is NOT near the MAS air sensor, but on the other side (drivers side) on the fender well. So are the other connectors you will need to integrate circuts with.

Wire Details:
BEFORE YOU START:
1) Check out my diagrams for compatability with your system - They should be correct, but check.

2) Go to the junk yard, one where you "pull it yourself" and get a bunch of different connectors as extras. You will thank me later. Besides, they come in handy if you add other accessories like compressor and lights...

You may not find the Brown connectors,there are gray ones with the same key pattern. Get at least two of these plus the other 8-pin and 4 pin connectors. They are easy to find on Explorers, Bronco's and any other Ford.

3) Buy some dielectric grease at the auto parts store. Use it on ALL engine compartment connectors to prevent corrosion (oxidation) and water intrusion.

4) Get some shrink wrap tubing, proper solder and soldering iron. Please use solder and crimp connections with shrink wrap insulation. DON'T use the crimp connectors from Radio Shack, they are too cheap and prone to failure, the insulation will fail in the harsh engine compartment.


There is ONE brown connector on the main engine harness that has circuts that go to several different connectors (one BROWN 8-pin, 2 GRAY 8-pin) located on the driver side fender well. The water temp connects through a black 4-pin connector near the battery.


BROWN V8 Main Engine Harness Connector:
Located in engine compartment, driver side fender well --> Explorer Body Harness Connector

1) EEC relay, 12V crank & run (R/LG) --> Brown connector: power on run (O/BK wire)

2) E-Coil & EECA (T/Y) --> Brown connector: Tach (T/Y)

3) Oil Pressure Sender (W/R) --> Gray Connector: Oil Pressure (W/R)

4) 12V crank Only (W/P) --> Gray Connector 1: Start Relay (P/K)

5) 12 Volt crank only (R/LB) --> gray connector 1: Start Relay Ignition ((R/LB)

NOTE: 4 & 5 are jumpered together in the original engine harness.

6) Neutral Sense switch + (LB/Y) --> Gray connector 2 (GY/R)

7) Neutral Sense switch - (GY/R) --> Gray connector 2 (B/Y)

NOTE: Neutral Sense switch - Some transmissions don't have this circut. It is NOT ESSENTIAL to run. It is necesary to extract EEC codes. You can hook it up #6 & #7 through a togle switch and leave it in the engine compartment till you need to extract codes. The default position can be left OFF. Close it "ON" for diagnostic use only.

8) H2O temp Sensor (R/W) --> Goes to a BLACK 4 pin connector located near the original battery location (BK/B)

OPTION: you can trace this wire back to the driver side of the wire harness and splice it in there (use a connector).



GREEN 8-pin engine harness CONNECTOR:
Located inside cab, passenger side wheel well near the EEC IV ECU --> original body harness connector

1) A/C Heater control (P) --> Black 4 pin connector above ECU A/C heater control (P)

2) Fuel Pump Inertia Switch --> Fuel Pump Inertia switch on passenger foot well - 2 pin socket at switch (GR/Y)

3) VSS + (GY/BK) --> 2 connections: a) Black 4 pin connector above ECU (GY/BK); b) small 4 pin connector in engine compartment driver side fender well (GY/BK)

4) VSS - ( PK/O) --. 2 connectorsL a) Black 4 pin connector above ECU (PK/O); b) small 4 pin connector in engine compartment driver side fender well (PK/O)

5) Low Oil Sender (W/PK) - NOT USED / OPTIONAL.

6) RUN ONLY HEGO POWER (GY/Y) --> Brown connector on driver side fender well HEGO power (O/BK)
**Note wire color difference

7) Check Engine Light [MIL] (PK/LG) --> Brown connector on driver side fender well Check Engine / EEC Test (T/R)
** note wire color difference.



OTHER:
I had to Add - Modify the following:

1) Wire from Fuel Pump Inertia switch on passenger foot well (PK/BK) --> engine compartment 4 pin connector on wheel well [same as VSS circut]: Fuel Pump (PK/BK)
** this completed the inertia switch circut.

2) Rear Defrost circut:
From 4 pin connector above ECU (GY/B) --> Black 4 pin connector (large) near battery (GY/LB)
** This is a heavy guage wire - higher amperage for window defroster.

3) Low Oil Sender circut [optional]:
I did use the low oil sender, but connected it from the low oil sender on the oil pan (W/PK) --> gray connector 1 on the fender well with the oil pressure and power on start circuts (W/PK)

4) Transmission Back Up light:
The gray connector 1 also contains the transmission back up light circut. You will retain this. It is a two wire set up: (BK/PK) & (P/O)

5) Above I mentioned a black 4 pin connsctor for the VSS -, VSS +, and Fuel Pump. It ALSO contains a ground wire that is connected at the battery negative pole.

6) The Main Engine Harness should have 2 power leads that connect the FuelPump Relay and the EEC Relay to the battery POSITIVE side. From some set ups,like a mustang or the FMS harness kit these are FUSED LINKS. That is, there is a slow fuse link in the end of wire harness at the battery connection. You have 2 choices:

A) Connect these links directly to the power source:
Dark Brown & Black wires [very thick] can be connecteddirectly to the POSITIVEside of the battery,or the where the positive battery lead conncets to the starter relay [whichever is closest].

B) Remove the fused link (the thick part of the wire with the shrink wrap) and connect these circuts through the Explorer wire harness.
The Black 4 pin connector near the battery [the one that also contins the rear defroster circut] also contains these circuts but runs them through the Main Distribution / fuse Block which contains the proper slow fuses.
* The EEC Relay (Y) --> EEC power relay (Y) on the black 4 pin connector
* The Fuel Pump Relay (PK/BK) --> Fuel Pump Power (BK/Y) on the black 4 pin connector.

7) GROUND circuts:
Make sure the following ground connections are GOOD.
a) Battery Negative to FRAME RAIL & ENGINE
b) ENGINE [or FRAME] to Body
c) ECU Ground (B/W) from engine harness --> Battery NEGATIVE post ** VERY IMPORTANT


After you are done you can wrap your wires with plastic wire wrap and electric tape as desired.

NOTE:
There are some circuts you can run in a more direct fashion, but you MUST make sure you connect them in the right place and and on the load side of the circut breaker. If you go through the connectors as mentioned there are "no troubles mate".

 

[86caprirs]

So this is for putting the mustang harness into the Explorer harness?????I was thinking of doing a T-bird harness from the t-bird i grab the trans and engine from.
Is the t-bird harness easier or harder to do?????

 

[Guy Groves]

The T-Bird is a popular option for this kind of swap.

The T-Bird is essentially the same as far as the wire harness goes for the 5.0 HO engine. I recommend you get a good wire diagram for the years in question and compare them. You will have to make the same modifications I have listed, no more. The wire and connector color / bundeling may be a little different. Also I believe the T-Bird might have some additional wires in the engine harness that are for accessories. You can ignore them or use them for your own accessories if you desire.

Note: Ford started to standardize their wire colors in 1989 but did not really finish this task until about 94 or 95 ( I worked for Computervision at the time, we supplied software to design wire harneses to Ford). You will notice that most of the wire bundeling has a common color sheme with some minor differences.

The connectors and grouping of wires in bundeles changes with each vehicle for things like AC, Alternator, accessories, transmission lead because of the unique geometry of the vehicle.

Definatly use the T-Bird engine, trans, and wire harness. (Actually I might consiuder a different tranny).

If you don't know the history of the doner (You get it from a junk yard) I would highly recommend the following.

1) Get the engine bench tested, maby even have your wrench go over it carefully. This might be a good time to have a valve reconditioning done, or complete valve job. I broke my doner down all the way to inspect the bottom end (crank, rods and pistons) and then had my heads cleaned, machined, valve reconditioning (didn't need new valves), and head porting done. It only cost a few hundred dollars. I now have over 30K miles on it without ANY incidences.

2) Test EVERY circuit in the wire harness. A simple continuity test will tell you a lot about the harness (you will know it inside-out) and electrical problems can cause the most fun project to turn into a nightmare. Testing that all circuits are good (have continuity) and a bit of repair on wire wrapping prior to installation is good insurance. If you are novice this should take a few evenings of testing in front of TV, with a beer (or two even).

Lastly, Dont get in a hurry. You will only make mistakes. Unless you have done this work more than just a few times then I would tell you to spend twice as much time planning and walking though it in your mind as you will spend on actually doing it, and make notes and an outline of the tasks to perform. This is not the most fun part, but I find that it will keep things on track once actually get started.


Some last minute thoughts:
1) Know what T-Bird engine you have! I believe there were several T-bird models that had the non-HO 5.0 engines? There may also be different ignition spark sequences. (Ford had at least two timing patterns for 5.0 & 5.4 engines, just make sure you know which one you have).

2) Get the right ECU (Engine Control Unit), this should come with your wire harness. The ECU MUST be compatable with the engine. For example, a "Mustang" ecu was built for the HO (roller lifters) engines. It is NOT compatable with a non-HO engines. There is some interchangability between units. I don't know about the T-Bird, do some research. For 5.0 Mustangs all the non-Cobra ECU's between 1989 and 1993 (even 94 & 95) are basically the same. The 89's were the most aggressive in terms of performance. As years went on they were required to meet higher fuel milage requirements, so performance was sacraficed for fuel mileage. The emmissions were all the same according to some engineers I have talked to. (My 1989 ECU exceeds the 1993 emmissions standard making the vehicle street legal in my state.)

3) O2 sensors: Get new ones, and make sure the wire harness is connected to the right ones. In some engines there are multiple O2 sensors forward and aft of the catalytic converter. If they are wired backwards the engine won't run very well, or at all. If there are 2 O2 sensors one for the left and right exhaust banks, get them wired properly as well. The wire harness diagram will indicate wich is for the left and right sides. I only mention this one because I know people who have hooked these up backwards and had problems that were very difficult to trace down.

4) Oil Pan. You may need to replace the oil pan with "double sump" type pan from a Mustang. This is easy enough to do, just make sure you replace the Pan and get the right oil pickup tube. (Ford is very bad about oil leaks at the oil pan and valve covers. Use GOOD gaskets and coat them with RTF, especially around the front and rear bearing areas. Use enough to make a good seal, and not so much that you get a lot of squeez-out inside the engine. The Torque down the parts properly! Improper torque pattern and overtightening WILL cause leaks.

Good luck, and have fun.
Guy

 

[86caprirs]

Thanks for the info.....But tell me about the trans????What should i use?????I want to be able to still use my stock transfer case.

 

[Guy Groves]

There are a couple of choices. You can bolt up a lot of tranny's to the 5.0 block. The T-5 standard Trans is popular, I don't know what is in your Bird.

Do some research on the T-Bird trans. Are you talking auto or stick (auto I presume)? What are your requirements? If you do real wheelin will the T-Bird Trans handle the demands? If you don't go off road and only use your 4x4 occasionally in the snow kind of thing the tranny might be just right. I would be concerned with the torque converter and shift ponts used by the T-Bird. The may be too "sedan" like to work well in the Explorer. You can always get a more aggresive torque converter that locks up better (If that is what you want). I don't know what might be available to reprogram the shift points, if anything, or if it would even be necessary.

Do you do any towing, can the T-Bird Tranny take it?

I wanted a standard transmission that was durable, had a 4:1 first gear (or lower) and was not as heavy or large as the Z transmissions. It should also allow me to upgrade my differential at a later time. It needed to be low cost to buy and repair.

I opted for a standard Trans. From an F-150 (another Mazda made trans.), but stronger than the stock 4.0 Mazda trans. and not as massive as the Z trans. I also had the shift cover replaced with a newer model that had the shifter located about 1.5" further back.

I am "pleased" with my decission. There has only been on or two occasions when I would have liked the Z transmission with its very low granny 1st gear.
The Mazda transmission is strong enough (built to go behind V-8 5.0 & 5.4 engines. can withstand relativly high torque. On the downside it is a Mazda built tranny which have a relativly bad reputation. 1st to 2nd syncro's seem to go bad over time so you need to be a little gentle.

Advanced Adapters builds a variety of adapters. There is one available to bolt the F-150 style transmission (Full size Ford Transmissions) to the stock Explorer transfer case (Summit Racing sold it a significant discount).

 

[CDW6212R]

Excellent responses, I wish I could get detailed help like this.

Start by buying some service DVD's, look on Ebay. They aren't quite as good as the factory versions, but those cost hundreds of dollars each.

Don't use a thunderbird AOD in an Explorer, the internal parts aren't good enough. They can be upgraded, but it would be cheaper to get an AOD from a Mustang or Mark VII. Good luck,
Don

 

[86caprirs]

Thanks guys. How about an automatic from a F-150 or Bronco????I know the stock transfercase from the Explorer will not fit,but the fullsize transfercase is to big.
The Explorer is just strickly a highway/freeway driver with the occasional lock into 4x4 for the snow. I will not be towing with it,i have a Dodge Dakota v8 to beat on for the towing.I just want a reliable driver with the V8 power......And before you say that i can hop up the 4.0L cheaper, i look at the 302 for power and durabillity and an AOD that is alot stronger than the A4LD.The diff is an 8.8 with 3.55:1 locking and i may swap for the disc diff in the future. I am happy with the Explorer and i also am a tech for Ford too so parts will be alot cheaper when it comes to repairs.
Thanks guys
Shane

 

[410Fortune]

Wow nice thread.
Ditch those 3.55 gears when you get a chance and go 3.73

the fullsize T case has been made to work, it BARELY fits between the frame rails, I think the case I saw was a BW 1356 from a Expedition.

 

[Guy Groves]

If you are going to a 5.0 the 3.55gears will be good on the road, but not low enough for any serious off road.

The auto from an F-150 would probably work.
With any conversion one thing you really need to consider is the lengths of the components and where they land in your vehicle.

Different motor mounts will mount the engine in different positions fore and aft, I've seen up to 1.5 inch difference.

The F-150 has a rather short length between the engine block and the transmission stick location. You will need to make some measurements to see where the shifter (auto or manual) will be positioned in the cab.

Transfer case
The stock transfer case for the F-150 / full size Bronco is quite a bit larger than the stock explorer. It does NOT fit well between the frame rails of the early explorer. You WILL have to modify the case by trimming off some of the aluminum protusions on the case. You may still have some interference with the rails, which might require that you trim the frame rail and then re-enforce it. Another option is to drop the engine and transfer case as low as possible, or rotate the transfer case (not suggested). You can drop the transmission mount, but it might change the angle of the driveshaft enough that you will need to also adjust the angle of the rear differential. Ideally you want the U-join plate on the differential to be parallel to the one on the transfer case (within 1 degree), or you will have U-joint longevity problems.

Advanced adapters makes an adapter (I think I paid $450 from Summit Racing) to mount the full size ford transmissions to the smaller transfer case from the explorer. Check out the advance adapter catalog in the broncoII explorer section. I couldn't find any specs on thransmission, but some techs at a transmission shop say that the transfer cases are not that much different and the real difference is the internal chain (which is the same width and chain spacing, just a little longer).

I have an F-150 5 speed transmission mounted to my stock explorer transfer case and have not had any problems. I am concerned and I try and take care of it (don;t abuse it). The plan is that someday I wil replace it with an Atlas.

Another thoughts:
You are adding about 175# to the front suspension. The Explorer 4x4 has a bit stiffer suspension that should handle it, but it is marginal. I also have a Superlift kit on mine, and the springs are not really up to the task (too light). I have gone to Rancho 9000 shocks which help. Ideally I need to get some custom springs made.

You will need to make som modifiactions to the firewall and possible the transmission well. A 3# hammer works well. Use 2 of them, one as an anvil that you place against the body and the other to hammer with. It will make a smoother modification (tehere are special body anvils that you can get that will form a smoother surface, but I don't think it's worth the effort).

 

[Creager]

i think this thread needs to go to the useful thread section huhuhuhu

 

[86caprirs]

So i can use the 5.0L engine and trans from the F-150 from a 92-95 and use my stock transfer case with this combo??????Is it easier to do the wiring into the X with the F-150 harness as long as it is still EEC4????? If i can i need to know. I want to do this swap now that my trans will not shift into OD.



And how do we put this in the usefull thread section??????

 

[410Fortune]

Advance Adapters makes tailshaft and adapter housings that allow you to run the BW1354 T case with a AOD, AODE or AODE-W (4R70W)

The Borg Warner 1354 transfer case is the electric shift model found in most V6 4x4 Ranger based trucks (Bii, Ranger, Explorer)
Basically the full size transmissions use a 6 bolt transfer case and the V6 use a 5 bolt.

The transmission must be taken apart and the new tailshaft installed for most applications.
Expect to pay $450+ for the part and $300+ for the basic install.
There are other varaitons available

 

[86caprirs]

Well the trans in a pick up is heavy duty right????It is not an aod but called something else???E4OD????It would have an OD button on the shifter of the F-150.Or is this the same trans in the lincoln LSC???

 

[86caprirs]

Or is this the same as the trany's you are mentioning?????

 

[410Fortune]

If you use a E4)D, if yuo can get it to fit (I have heard that sucker is toooooo big for our conversions, but would have to go search around to make sure) then you can probably get the transfer case with it to fit as well, body lift, floor modifications, trans tunnel "clearancing", frame notching, t case indexing ring, all sorts of things are possible and have been done. But why not use a donor trans that has been proven to fit and wrook well time and time again in 5.0L conversions?

the 4R70W I just installed is a TIGHT fit in my 88 with a 5.0L, it fits good, but under there it is a monster compared to the V6 trans, so I wouldnt want to imagine anything larger.

 

[CDW6212R]

I am not sure if Ford used both the AODE and E4OD in those 90's F150's. A friend of mine has a 93 F150 I believe, with the AODE. Look at the pan, or the door jamb, and find out what it is. Don't try to use an E4OD, those are huge, and are in the Lightnings.

The early 90's F150 AODE received the first wider OD band. That required a change of a couple of other parts. I bought those new for $300, and installed them into my 91 Mark VII AOD.
Those AODE's also got the four intermediate clutches, and they have "B" OD servos(Thunderbirds came with "C" OD servos). Anotherwords, those are good choices, the AODE's. Make sure you use the matching PCM, and install a trans cooler and filter.

Probably all of the 302 4x4 Explorers have 3.73 gears. Choose at least that high of a ratio, and higher if you install tires taller than 29". Good luck,
Don

 

[86caprirs]

I want to install a V8/auto trans swap with the use of my electronic transfer case.I just don't know which is the best combo or vehical to get it from.I guess i will us the lincoln marc 7 with eec harness.....I just want durabillity.The X will be just a daily driver that will see mostly hiway driving.Just some people say stay away from the aod in the t-bird/cougar but use the one from a LSC/mustang......i don't know what the differeces are.The 5.0L in the t-bird/cougar has the short accessory but i just want to find 1 car to remove everything.
Shane

 

[410Fortune]

Your best donor would be a GT-40 Explorer drivetrain, pushrod EFI 5.0L and 4r70w.

this is the cheapest 5.0L to use.

 

[86caprirs]

finding that 5.0L explorer engine combo is like you finding a Tim Horton's in your town.