I liked our Expedition in that it is a really nice people mover around town and on family trips. The AWD makes it great for getting up to the mountain for snowboarding. But the downside is that it used a lot of fuel. I started thinking about a diesel swap and found the 4BTSwaps site. Lurked there for over a year while I found an engine, transmission and some other parts needed for this swap. Started at the end of August in 2010 and made the first drive at the end of November.

I replaced the 4R70W with an M5R2 from a 1990 F-150. The engine came with a Ford adapter that did not work with the newer modular transmissions. The M5R2 bolted right up to the stock 2003 transfer case. I chose the manual to save money and to have something unique. To use the auto trans would have added about $3k to the swap (belhousing adapter, torque converter re-work, and aftermkt trans controller).

This has been a good swap. The SUV now gets about 24mpg hiway and 20mpg around town. I think this could be improved if I changed the gearing from the 3.73 ratio to 3.55 and made some minor adjustments to the VE pump. The best I ever got with the 5.4L was about 17mpg on the hiway. So I have improved the fuel efficiency about 60% and the cost of fuel is an additional 10%. I'll take it. Plus it is a hoot to drive!

There are more details on the 4BT Swap site; so I will start with the basics here. If there are specific questions, I will try to answer them here.

First, you must get rid of the gasoline burner:


The 4BT is much wider at the bottom than the V8, so the motor mounts must be cut off, shortened and re-welded back to the frame-- with appropriate gusseting.



The passenger side mount has been moved forward a bit, to allow for the long starter on the 4BT. The stock isolators from the V8 are mated to custom mounts bolted to the 4BT block. On the passenger side, the mount fits between the starter and the AC compressor, with a little room leftover for the turbo drain.



The driver's side was pretty simple, nothing in the way, just a plate and an angled surface for the isolator:


The passenger side was more involved. There are two pieces of bar stock drilled through on the LH side that make the plate stand off from the block at that location and tight against the block at the three holes on the RH side. The three lugs are mounts for the AC compressor:


Here is a shot of the p-side mount plate ready to go:


The transmission was within 1/4" of the same length as the auto trans, but the support was a couple of inches away from the location for the stock trans. No problem-- I just made a cantilevered mount from 1/4" plate.


I measured the engine bay six ways from Sunday before starting to make sure there was going to be room for the taller inline four. There is room to spare from the bottom of the cowling (under the windshield) to top of the front axle (a couple of inches), but it is not possible to get the engine shoehorned in there without some sheetmetal modifications on the oil pan. There were 6 or 8 trips in and out of the engine bay to get this far, but with each trip in and out, I worked on the motor mounts at the same time.





Once the engine was in it's new home, there was a month or so of taking care of the fuel tank, new fuel lines, wiring, cooling, intercooler and exhaust runs. Here is a shot of it pretty much done:

 

I bought some parts from a local guy that parted out 6BTs for fun and profit--the vacuum pump/steering pump combo, and some other small parts. He suggested I put a 6BT in, since I would have more HP to build on. I nixed that, since I already had the 4BT and I did not want to deal with the extra weight. Well then I went about setting in the inline four and quickly saw that a 6BT would only go in with some major sheetmetal work. So that idea is one for those guys that have a lot of time on their hands; but I wanted to get the project done so it could be a daily driver again.

Here is a shot of the engine with the flywheel and front pulley on. Not going in like this!


With the front pulley off, there is barely room to get it down under the cowling. This is with the clutch disc and pressure plate removed also.


The next problem was the rear lift eye was too tall and my lift chain made too much of an inverted "V" to get the rear of the engine under the cowling.


I needed to make a swivel hook to get a little more freedom while positioning the engine, so I used a chain binder and a swivel eye on the end of my hoist:


This allowed me to turn the engine sideways to get it down the hole, then put the clutch on once it was down. Then I could turn the engine 90°, lower it a little more and connect to the transmission.


To make all this work, I had to cut down the rear lift eye so the boom on the hoist was as close as possible to the valve covers. If I ever do this agian, I will spend some time to make a lift bar to get the lift point and swivel a little closer to the valve covers.

 

Nice writeup. Been thinking about a Cummins for my 85 F150 for some time now, just debating on the 4 or 6. Hows the power compared the the 5.4? Where did you find the 4bt? Been looking for one for a little while, but not real seriously yet. Been lurking over on the Cummins Diesel and 4BT websites for almost a year now.

 

Sweet project - this is definitely getting nominated for the tech folder. Although I'm starting to wonder if it's only going to be 4BTs in there

 

So great to see this.i dont know y we all arent doing it.expeditions are dirt cheap.and i just bought a 4b for 100$....but i then sold it on flebay for 500it so i avoided more work...great write up and get it done!

 

The low-end torque is awesome; better than the 5.4L. It does not have the top-end HP that the gasser had. For example, we took a family trip to southern CA to visit the worlds greediest mouse (aka Disneyland). With all seven of us and our luggage, the Expy weighed in at 7200 lb. So no doubt some of you will want to make a joke about 7 dwarfs. Go ahead, I can assure you we are not small in stature nor insecure. Going over the Siskyous on I-5 I would have to shift down to 4th and the speed would drop to about 55-60 mph at full throttle; so I'm still basically keeping up with traffic but I could not whip out in the passing lane and pass anyone I wanted. Then going south on the Grapevine, the bottom part is the steepest and I dropped to 50mph at the steepest part. But mid-grade the slope decreases and I could shift back into 5th and go 65mph again.

I have pulled a couple of small utility trailers and you can definitely tell they are back there when going up a hill.

I think this problem could be solved with some of the common mods: smaller turbine section or turbo change from a 1st gen 6BT, turn up the fuel, advance the timing, etc. it is possible to get close to 200hp with these simple mods, and the torque goes up accordingly. So that would let me change my final drive ratio from 3.73 to 3.55 and drop 100 rpm to go the same speed. This means that instead of turning 2000 rpm at 65mph, I would be turning 1900 which puts me closer to the sweet spot for lowest fuel consumption. In most of Oregon, the speed limit is 60, so I would be right at the peak of torque and fuel efficiency.

I found my engine on Craigslist, from a guy that bought a bunch of bread vans at auction some years ago. This was the last one he had and he was done with projects and decided to sell it. I bought it with the starter and Ford transmission bellhousing.

As for your descision about a 4 or 6BT-- it depends on what you will be doing with it and the price of 4BTs in your area. If you are towing, I would lean towards the 6 cyl. In my area the 6BTs are easier to find and cheaper as well.

 

I re-used three sensors from the V8: the oil pressure sensor (actually a switch, not a pressure transducer), the coolant temperature sensor, and the crank position sensor.

The oil pressure sensor was the easiest; it had an NPT thread and just screwed into the port under the oil filter as shown in the picture above (6th from top, right under the oil filter).

The coolant temperature sensor (when it was in the V8) was designed so that the end of the probe was in direct contact with the aluminum head, with some of the cylindrical section of the probe surrounded by coolant. I drilled and tapped an NPT plug in the center with the metric straight thread for the Ford sensor and put it in the same location that held the former sensor for the bread van application. This is the stainless fitting between the heater hose and the thermostat housing below. In the new location, the sensor tip does not contact anything but coolant, and it works fine.


In the bottom of the photo above, you can see the crank position sensor in it's new home. I used a dampener pulley from a 6BT and machined the same pattern of teeth on the OD as was on the crank of the 5.4L engine. This is 35 teeth on a 360° pattern. So in one spot there is a tooth missing. This is so the PCM can recognize one revolution when the missing tooth goes by. The PCM counts the other teeth with respect to time, and can discern if the rotational pulses are as they should be. The screenshot below shows this pattern:


In the photo below, you see the stock sensor in a new mount. The tip is about 0.030" from the surface of the dampener.



This allows my factory tach to work. I don't get any error messages by not having the cam position sensor. I had to extend the harness wires about 3' to get them down to the sensor. One wire was shielded, so I found some shielded wire for my extention so that I would not pick up any stray signals. Although without spark plugs this may not have been a problem-- I just wanted to avoid giving myself gremlins to chase around.

Here is the quote from the Ford manual which explains what the PCM is looking for with the 35-pulse/rev.:

 

The one problem someone in New York would have with such a new vehicle is that there's no way to pass emissions without being OBD-II compliant.

Anything from 1996 and up has to be, here.

Interesting reading: United States emission standards - Wikipedia, the free encyclopedia although it doesn't say anything about New York which is yearly OBD-II testing for light-duty gassers.

And even though you put a diesel in it, it's still considered a "gasser" because of the OEM equipment.

But enough of that, back to the tech!

 

The emmissions test is not required in most of Oregon-- only in the Portland area. That would definately make this swap a no-go.

 

Thanks for the reply.
The 6 is easier to find around here also, and probably cheaper.
Wont be doing much towing, at least that's the current plan. It will mostly be light hauling and a street truck. Glad to hear the 4bt can do the job in yours as mine will probably be about 3000lbs lighter.

 

Nicely done on the tach sensor ring & the swap as a whole. After owning (& quickly selling!) a 2001 4wd expedition I'm not sure I'd be putting the time to swap one of these nice motors in, but you are definitely doing a nice job of it.

 

Thanks! Coming from you-- that is a really nice compliment.
CR

 

Hey CR, Great Job on the Swap!

I would encourage doing some of the performance mods on the pump, They are easy to do and you will be very impressed with the performance gains! Install a 3200 Gov Spring, a Denny T Power Pin and turn the fuel up a little. I didnt notice what you have for exhaust but make it as free flowing as you can stand the noise. Right now you are at 105 HP, with some of those mods you can hit 170 pretty easily. And as you stated earlier, you can hit 200 with a 6BT turbo. You will want to get Pyro and Boost gauges as well.

What MPG are you getting?

Again, Real nice job!

 

Thanks for the encouragement and kind words Darrin. I have the 3200rpm spring installed already. My engine is a 4BT with 17.5:1 compression ratio. I have added an intercooler which should provide my combustion with excess air without any other changes. The 4BT engines with factory intercoolers have 16.5:1 compression ratio. This tells me that I should not go crazy adding fuel until I have the pryrometer and boost gauges as you recommend.

I want to keep my factory gauges intact, so I have been looking for a 3-hole pillar gauge pod-- but it does not appear that anyone makes one for a 2003 Expedition. This means that I will have to take a 2-holer and add a 1-hole pod with fiberglass, bondo and blending. I need three gauges since the stock oil pressure gauge is a bit of a misnomer. It indicates "normal" if there is greater than 15 psi. I think that's lame so I want to know what my real oil pressure is. All this takes time and since the vehicle is a daily driver I am not in a huge hurry to get the gauges done and crank up the fuel. Eventually curiosity will get to me and I will do the simple mods.

My exhaust is a 3" straight pipe that runs over the back axle like the stock exhaust system. If someone else is driving and I sit in the second row seat I think to myself "man this is kinda loud; I gotta put a muffler on this thing". But--when the weather is nice, I roll down the passenger side rear window to listen to the snorts and grunts. Then I'm thinking "why would I ever put a muffler on this--- it sounds so cool!".

I did not end up with very much room from the back of the turbo to the firewall. This was forced by the position of the shift lever in the cab. If I moved the engine forward a little more, then I would have had the shift lever coming out through the air mixing duct/box/thing under the dash. So this is what I had to work with-- 105mm or just over 4":


I fabricated my own cobra-head fitting, with the flow area of the boxed section greater than that of the 3" tube. Since there is a plastic duct/vent on the firewall right where the hot parts live, I added a piece of aluminum sheet on stand-offs to shield the plastic. It's working so far.


Here are a couple of shots of the fabricated downpipe. The v-band flange connects to the run under the cab.




I made a hanger and a short weed-burner exhaust as a temporary situation until I could get the complete run done.


I had a muffler shop cut down this temporary pipe upstream of the elbow, and make the remainder of the run that goes through the same place the stock muffler used to live, over the back axle and out the side. I gave him my catalytic converters and O2 sensors and $100 and it was done. The run through the muffler cavity is straight with a hanger in front and in back of where a muffler would easily go if the day comes that I think it is more obnoxious than fun-sounding.

 

F serious gauge pods wont fit? Thought they were the same, what I get for thinking.