It's time!! I've got almost 1000 miles on my ZF6 converted Excursion now and I've been waiting for some free time to do my part for the community and fill in some of the gaps that haven't been detailed closely in other threads. Background: I have a 2002 RWD Excursion with 7.3 that I've owned since Summer of 2017. I bought it with around 214k miles on it and on the day I began the swap the odometer read something like 246k. The 4R100 in it appeared to be working fine, but I am a die hard stick shifter and I have plans for the truck that may have necessitated some expensive beefing of the trans so I decided to dump that money into some stupid stuff like a ZF6!




This swap is not that technically complex thanks to the Ex obviously being heavily, heavily based on an F250 Super Duty which was sold with the ZF6 for many years. From my research on this forum an the pirate4x4.com forum, it seems people are very interested in this conversion, but I see very few people try it. Certainly faaarr less than convert their Super Duties in this way. I suspect this is due to people's concern with the electrical part of the conversion which on a 4x4, I think it is possible nobody has figured out how to make the shift on the fly 4wd work yet... But if you have a 2WD like me, it's not so bad. I am an electrical engineer in the off highway equipment/ag industry so automotive electrical systems don't scare me. Cutting a big feckin hole in my floor does!!! :O I'll talk about the electrical in more detail than some of the other threads have and hopefully that will embolden some people to take on this swap and preserve the manual gearbox!




And before I get going, I will apologize for the lack of pictures...I was s#itting bricks for an entire weekend of working and hardly touched my phone. I'll take some more finished pics and add them later.




What you need:




Budget: First, you need a big budget. This swap is not cheap to do right. My intent was to make it as absolutely factory as possible not just for aesthetics, but for longevity! I tried to do it on a shoestring with a $2500 budget to start but you'll see why by the end this project cost me around $5000.





Transmission: You need a ZF6 trans, new, used, or somewhere in between one way or another. I bought mine on craigslist for $800. I was told it was from a fleet maintained truck but I ended up taking home a transmission that appeared to be locked up rock solid and appeared to have rust inside on the gear teeth. Probably from a flooded truck. I ended up using it as a core on a reman with Whatever It Takes transmission company. That was not what I hoped because that new trans cost me $1925 (I got it on a local transmission shop's account). Total cost: $2725... which is almost 300 better than a new one. Normally cores go for at least $1000 from what I have seen, so I probably still saved 200-400 clams here.




Below, how I tried with all my freaking might to make this trans rotate. Nope. She was dead.













Floor hump: If you're researching this conversion, you'll likely have seen in other threads the ZF6 is much taller and pokes through the original floor by a handful of inches. I got the floor hump from the same truck the trans came out of. The seller cut the floor out in the shape I requested and I picked it up with the trans. I felt like I should sneak up on the size of the hole I cut in the floor, but it just meant it took us ages to get the hole big enough and as we got the trans closer and closer to installed position, we had to eek out more and more metal. I ended up cutting out like a legal size sheet of paper from the floor. I wish i had a pic...

Below, the original floor


Below, the manual floor. The new floor needed massaging on the passenger side to fit correctly due to the shape the seller cut out on that side. It can be done in a way that matches our floor just right, but that is difficult to communicate to someone just selling you parts from a junked truck. Once we got it shaped right, we mocked it up about 5 billion times to be sure it was right. Then we mocked it up one more time, drilled holes in the new floor where we wanted to place rivets, and then used them as pilot holes to drill the floor out. We then mocked it up again with the rivets pushed in. Then we took it off, sealed the heckin heck out of it with 3M automotive seam sealer goo and set all the rivets. Around 13 of them.

When we were finally done many, many hours later, the carpet pulled right back over the hump pretty nicely. There is a sizeable wrinkle on the side of the hump in the driver footwell that is kinda in the way of my go pedal foot but I already got used to it. Solution ideas are welcome for how to reshape the molded carpet. I might try steam and then smashing it flat with weight. OR if I stumbled across an F250 Lariat ZF6 truck with medium parchment carpet I could splice the whole front row carpet in! That would be sick!!



Sound deadening: I cut a yuge hole in the floor of my bus...so the sound deadening is worse than before. There's notably more 7.3 clatter inside and road noise at highway speed is increased. I plan to get a thin rubber mat, cut a hole in it for the shape of the shifter turret and lay it down inside the white floor hump to close off the giant hole in the original floor. On top of that, I'll stuff the inside of the white hump with acoustic foam until its bursting at the seams. Those improvements with the OEM shifter boot, should get me back to normal. I'll probably throw some more cheap dynamat knockoff material around on the floor while I'm there.


Shifter bits: I bought Ford OEM shifter bits on Amazon for a lot of money. Around 200 doll hairs for the boot, the shifter and the ****. Again, all in the name of an OEM solution.

Clutch: I got a South Bend clutch rated for 400hp. I like the way it drives very much. Someday I'll have almost 400hp so it's perfect. I also bought a new clutch arm pivot. Make sure you get the later model clutch arm because the old ones break. I got the clutch arm from the previously mentioned junk truck and it was the later one. Yay! The clutch kit comes with everything else you need even all the hardware. I think it was like $700.


Crossmember: The crossmember is notttttt I repeat NOT the same as a Super Duty. I am not positive why and I am not sure a SD ZF6 cross member works. Almost as fun as cutting a hole in the floor, you have to cut out the 2 holes for the trans mount posts. This took much slotting and trial and error. There is a square reinforcement plate inside the crossmember welded to the upper stamping portion of the weldment that makes it extra fun. I don't have any pictures of this but the other threads do. The front edge of the cross member will hit the bottom of the trans tailshaft housing as there is a vertical gusset hanging down from the trans there. A tiny amount of grinding gives the needed clearance. Don't forget like I did. The NVH is outrageous!!

Transmission cooler: (notes added 5/22/19) Forgot to add this part last night. Other threads didn't give much detail on this so I went in a smidge blind. The ZF6 has a tiny gerotor pump in the front for circulating fluid up through the cooler built in the radiator. I *suspect* this function is less about cooling and actually more about warming. Since manuals don't generate nearly as much heat as autos, imagine you started your truck up on a cold morning in the winter. You have this huge 235lb mass of steel and 6 qts of gooey ATF that won't get warm on its own! You want that fluid to be up to temp to ensure proper function of the synchronizers for smooth shifting and longevity. I think the cooler is more of a warmer to get that fluid up to temp in a reasonable timeframe. For that reason, I did modify the lines by cutting them to a more useful shape and connecting them to the cooler side portion with some power steering return tube of size 5/16". I'll take a pic and post it here soon.

Driveshaft: I went into this without a driveshaft because I am a stupid 27 year old and I convinced myself I was able to use my factory driveshaft since all the other threads I read did. Well the 2WD 4R100 has a slip yoke in the tailshaft housing like many transmissions of such configurations. It was not until I put the transmissions on the floor next to each other that I realized this. And if you're 2WD like me, you need A LONG DRIVESHAFT!!! 72 inches flange to flange. Whoa. I tried to get them to custom make me a 4" diameter shaft which by my calculations would have gotten my critical speed PLENTY high for my comfort. But my guy could only get it done in 3.75" diameter which I was upset about. Though, now I have gone 85mph and it was fine and honestly don't intend to go much faster ever. Why would I? The custom shaft cost me a lot of money, $575. If you have a 4x4 truck it seems to me the length works fine with the ZF6.


Pedals: Pedals are pretty easy. I got the clutch pedal and the brake pedal assemblies from the craigslist truck with the other parts. The Excursion has the same firewall as a Super Duty so the studs and holes for the clutch pedal are there as well as the hole for the clutch master cylinder. Piece of cake. I installed these parts about 2 weeks before I started the real work. I decided not to swap the brake pedal out because I have the electric adjustable pedals and it looked annoying. Instead I plan to cut down the brake pedal pad to the size of the clutch, and I bought new OEM replacement pedal rubbers for both pedals. Looks OEM!

PCM: Your PCM is going to be pissed without a bunch of autotragic related components to play with. I sent mine off to DP Tuner and he reprogrammed my PCM with the needed changes as well as his 80hp canned tune and had it back to me in absolutely no time flat and gave me great customer support as well. Think this cost me around $250 (manual conversion, PATS and 80hp tune) plus shipping both ways. I needed to drive my truck to my buddy's shop 75 miles away so I borrowed a PCM from my friends 2000 F250 and it got me there fine then I returned his PCM. (While his truck was down, I left him my 2002 Corvette Z06 trackday car LOL)

Wiring: The wiring is the fun bit. It's not that bad! Especially without electronical shift on the fly 4x4. 3 main things need to change because you need to 1) start the engine, 2) have reverse lights, and C) cruise control.

1)the electronic transmission range selector has MANY switches inside. You only need to care about 2 of them the switch between pins 10 and 12 is the neutral safety switch that allows you to engage the starter only in Park or Neutral. You can just jump these wires forever, or you can do what I did and buy a clutch switch, extend these two wires into the cabin and splice them into the normally open contacts of the clutch switch. I ran the wiress through the grommet the range selector cable ran through and sealed the tube up. I like having a neutral safety switch. Even if you don't wire it in, you'll see why you may still want the clutch switch in a bit.
2)The reverse switch is between pins 9 and 11 and turns on the reverse lamps, and if you're like me and have a backup camera integrated with your nice radio head unit, turns on your backup cam. I bought an OEM reverse switch and pigtail and extended the wires from the range selector a few inches to reach.

The range selector wiring for the 4R100


C) For cruise, the only thing missing is the clutch switch input to the PCM. On an autotragic truck, that pin monitors the O/D cancel switch. If you push O/D off, cruise will quit. On an auto, that's a normally open switch. When your PCM becomes a manual, it works just like the manual Super Duty PCM so that pin is looking for a 12V signal at all times. That's where the clutch switch comes back in. The clutch switch has a second set of normally closed contacts for this function. All you have to do is when you remove the old range selector lever, extend the wires for the O/D switch down to the clutch switch and splice it in. Now cruise works and cancels as it should if you clutch in. See in the diagram below how this works. If you wanted, you could just short the wires together from the O/D switch but I do not reccommend this at all. If you are cruising, and forget how it works and happen to clutch in, I can't be sure if the PCM will be smart enough to realize something has gone wrong and quit cruise. If it doesn't, the PCM will see VSS decrease and increase fuel and you could potentially overspeed your engine.


Update 5/27/19
This weekend I got around to finishing the clutch switch wiring to make the cruise control work. Success! See the picture below, the little 3 pin connector for the gear selector stalk is taped to the main column wire bundle. When you take the stalk out and toss it in the lake, chop the red/yellow and tan/wht wires free. The red/yel is the 12v source for the stalk and the tan/wht is the switch input to the PCM for the OD cancel switch (in the manual PCM configuration it's the clutch switch for cruise cancel). The wht/grn is the ground for the OD OFF light in the stalk. I left it in the connector. Splice a pair of extension wires to them and run them down to the normally closed contacts of the clutch switch. Now cruise works! See my pic with the green dash icon below showing I'm crusing. Dope!




Transmission temp sender: The ZF6 doesn't have a temp sender in it like the 4R100 so the gauge now doesn't work and a red light comes on the dash to say CHECK GAGE which to me is a weird spelling for "gauge" but my Corvette says it that way too. Oh well. It's easy to fix but It's still on my list. The CHECK GAGE light is telling you the trans temp circuit is now open. Just close it up with a resistor! See below the image for the solenoid pack wiring table and the trans temp sender resistance table. Pins 7 and 8 are the signal and return wires for the sender. If I put a 10k ohm resistor in that circuit, it should satisfy the cluster light and make the gauge read "happy." I'll update once I've done this and confirm.

Update 5/27/19
Well I spliced a 10k resistor between the trans temp sender wires but it didnt fix the gauge or the CHECK GAGE light. Back to the drawing board. Ideas?





And then you're done! I wanted to go rip some sick burnouts but I really think the Excursion rear springs are toooo soft. The low gear torque is immense and the axle wrap is pretty bad I think and I'd rather not break things. Traction bars will be needed I am pretty sure. I will conclude by saying how much fun it is to drive and the people who know appreciate the truck for its uniqueness. You will love it if you go through with it and you might not go broke if you're a bit more careful than I am and buy some parts used. As I mentioned, I bought mostly new parts. Hopefully you guys liked my post and it drives some good discussion. If you're interested in this conversion and have questions don't hesistate to post them right here or PM me. I would like for a lot more people to do this! Again sorry for the lack of pictures, and if you see any gross typos or crappy formatting, I'm doing this on my 10" tablet and I'm going to come back and edit on my computer at work tomorrow!

 

And a seperate post to thank "gavan" of pirate4x4.com who documented his build a few years ago and the others who have contributed to a few threads on FTE. I was able to get very close to "expert" understanding in advance of this swap by reading those threads and really the only mystery was WHY I was making some of the wiring changes gavan talked about. As an EE I simply HAD to understand the changes before I was willing to go hack up my wiring harness so hopefully some people benefit from my explanations here.

And thanks to my friend Lucas who worked 24 total hours with me on a Saturday and Sunday to get the whole job (less driveshaft) done in one weekend. I have a terrible lumbar spine and can't do a lot of these things alone so his lifting help and metal working help really got us through a big project. And thanks to my friend Chuck who always lets me use his giant racecar shop in his backyard for basically free to do any and all outrageous projects on any of my cars any time.

 

That is awesome. More pics please!
If that OBD2 dongle is in the way you can buy a 90 degree plug with extention cord and zip tie it under the steering column. Mine was in the way of my big lead foot.

 

Thank you for documenting and sharing. I have read through Gavan’s thread on pirate a few times. I have a ZF-6 in an 04 donor sitting in a yard waiting for me. I appreciate your wiring clarifications.

Did you do anything in regards to the rear HVAC ducting?

 

Very, very nicely done!! Thanks for the wiring bits! I’ll be tackling a G56 conversion soon and hopefully some of your work will help translate. I had a 5R though, so we’ll see!

 

Thanks! I'll try to get some more pics for you guys tonight or tomorrow. As for the OBD2, I don't know if it's because I have small feet or what but I've actually never noticed it was there when driving!

An 04 eh? That would be an S6-750 from a 6.0 I take it. That sounds like a fun swap! Hopefully the wiring is the same for the 6.0 stuff! The rest should just be nuts and bolts really.

Thank you! Very cool! Curious why the G56 as I am not knowledgeable about that gearbox or the 5R110. Good luck! Post it up!

 

I added some stuff I forgot to the original post this morning about trans cooler lines and sound deadening and the carpet!

 

I originally wanted a ZF6-750, but the prices folks are wanting for them are outrageous. Also, I'm putting it behind a 12V Cummins, so adapters are also fairly expensive for putting a ZF6 behind a Cummins. If I would have found a deal on one, that would have been my route. Instead, I found a good deal on a local late model G56 (gear ratios are different on the older ones). The flywheel housing I already had works with the G56 as Dodge hasn't changed the bolt pattern in a million years. And, lucky for me, I didn't have to cut the hump out of my floor, just a hole big enough for the shifter (so far, not done yet). You can check out all the trials and tribulations in my build thread, which has turned into more of a resto-mod thread than anything else.

https://www.ford-trucks.com/forums/1...ld-thread.html

I'm interested in the diagrams you have for the transmission. Where did you find them? I have the wiring diagram book for 2003 Super Duty/Excursion, and it does not have that level of detail as far as the switches go (that I've found). Any insight or source for the 5R110 version? I'm alos going to try and figure out how to keep the electronic shift 4WD on mine if at all possible, but we'll see. It seems to be non-trivial.

 

Sick! 12V Cummins was the info I didn't know I didn't have. That's awesome I love 12V's especially in an Excursion. The G56 sounds like the way to go for sure on that. If you don't have to modify the floor that saves you hours on the conversion but I am sure there is plenty of other work relating to putting a Dodge/Cummins into a Ford. I think I found the 4R100 manuals in someone's google drive link under their signature here. One of the expert people who's always got the good stuff. If the 5R110 range selector is the same as on the 4R, then the wire pins will be the same. For ESOF, I am betting you just need to copy the implementation of the manual, 6.0 PSD clutch wiring as I believe for manual trucks the ESOF is looking for clutch pedal in to engage the transfer case.

 

Yep, the pickup is a 6.0. Bought it with a blown engine from a coworker for a steal. I currently have a V10 in the Excursion and the plan is an eventual Cummins, so a bit different scope than your swap.

Any comment in regards to my question about the rear HVAC ducting?

 

Ah yes! I forgot to mention. You have to remove the stock rear floor vent because it goes over the floor. The only alternative would be to add some flexible ducting through other routes under the carpet but it would interfere with the carpet laying properly on the floor. I elected to say "I don't have rear floor vents now"

 

daaaaaaaaamn That looks sweet.

 

Thank you!!

 

Nice write up!

I really need to do the wiring part of it on my Ex to get cruise control working. Of course I made it harder on myself because it didn't work before I pulled the V10 so I need to figure that out too haha.

 

I updated sections of the OP about clutch switch wiring and trans temp sender wiring today.