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Discussion Starter #1
In short I just converted my 07 expedition to a 4bt. It went well. Went with the m5r2 transmission. To see a full build thread go to powerstrokearmy.com and it's in the engine conversion threads.

Anyway I'm have issues getting the speedo and tach to operate. Anyone have any ideas?? Where is the VSS on this vehicle??


 

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Your truck probably had 2 VSS units. One on the transmission and the other on the rear axle. I believe the speedo got its info from the ABS sensor on the rear axle. The one on the transmission was probably to feed the transmission computer. Speedo and tach are fed through the ECM. It's probably needing a signal telling it the engine is running. I'm no computer person, but I feel sure there are others on here that have cured the same issue.
 

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Congrats on making this far! I don't know the answer to your question about the speed sensor (mine was in the 4R70W trans), but I would encourage you to get a manual on CD. I could not have done my swap without all the reference material from Ford. You can buy one for your 2007 from Helm Inc, here for $170:

http://www.helminc.com/helm/Result....&Category=15&Keyword=&Module=&selected_media=

Not trying to be critical, but you should take very good care of all the wires. Solder the splices and cover them with shrink-tubing. I even solder the crimp connectors and put shrink tube on top of the crimp. Then be sure every wire is in some sort of conduit that is secured to something that won't allow a lot of movement. The reason is that wiring problems on a swap can, and has in my case, left my wife stranded and needing a tow. As it turns out, the root cause was a wire between the PCM and the fuse box inside the cab failed and one end shorted to ground, which blew a fuse. I did no work on that wire, but it was spliced into the power side of the fuel pump relay, which I had tapped into to control the fuel solenoid on the injection pump. So this failure would have caused a tow job with or without the swap, since it used to run the fuel pump in the tank. It is an awful blow to the male ego to have my beloved bride get towed, and especially if it was caused by my own poor workmanship or oversight. Just trying to help a guy out here.

Keep us posted on your progress. Please post a picture of the shift lever when you can.

Cheers,

CR
 

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Discussion Starter #4
Thanks CR for your input!! Your build threads was an inspiration. Yes, thanks for the heads up on the wiring. I actually totally removed all of the wires I'm not using from the pcm plug. A little probe with a tiny screwdriver and they come right out. The final wiring will be sheathed and secured, I know that pic doesn't show that. I can only think of 3 wire breaks/splices so far. As for the console, its not done yet. The 3rd gens have a console shifter, so I think my finished product will look nice. I plan on making a custom linkage that will put the shifter up through the original console shift hole. But as of right now its functional. I already have a h1c turbo, 5x14 injectors, and 4" exhaust. I have gauges too just need to install them. She goes pretty good. I now know for a fact that there is no VSS on the rear diff. I looked and looked on it and saw nothing. So the VSS must be in the old 6r75 trans. So I'll get a vss from ford and machine a ring or whatever the sensor reads off of and hopefully be set. That manual would be nice!! The Haynes manual stinks!!! I'll try to keep this updated.
 

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Sorry I wish I could help but I really want to hear more of your build on why you had to change from the stock trans? I am looking to do my 05 Expedition. What kind of MPG are you getting and how is the driveablity? How much did you spend on the conversion?
 

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Discussion Starter #7
Sorry I wish I could help but I really want to hear more of your build on why you had to change from the stock trans? I am looking to do my 05 Expedition. What kind of MPG are you getting and how is the driveablity? How much did you spend on the conversion?
I put a link in my thread to my build page. I didnt necessarily have to change to a manual trans, it was purely personal preference. I would have had to make a trans to engine adapter though which wouldnt have been a big deal to me, as im somewhat handy on machining. Manual trans also helps the MPG factor. Im in the ball park of 25mpg. Me and my wife both enjoy driving it. It pulls good down low, but lacks a bit up top. it will still cruise nicely down the interstate at 70mph. Ive had a few bumps along the way, but id do it all again. I still dont have all the bugs hammered out, but im getting there. If i recall correctly the 2nd gen(like your 05) is easier to get the bugs worked out. Im pretty sure your original trans would work, but it will require having it programmed to work right. Might need to regear your diffs to bring down the engine rpm a bit. Ive dumped a bit extra money into mine to get it where it is today. I think if you were patient when buying stuff you could get it going down the road for 4-5k. I probably have close to 7k in mine. Also depends on how handy you are with doing stuff yourself.
 

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Did you ever get the speedo working? I'm doing a diesel/manual swap in my Sport Trac and it doesn't get the vss from the abs on the rear axle, but from the output shaft on the trans. I plan on making a tone ring on the driveline.
 

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Discussion Starter #9
Yep i got my factory speedo working. Apparently it gets its signal from the ABS sensors, but somehow requires the transmission control module to do its thing. So basically i have a TCM floating around in the engine compartment; in addition to that i have to have the transmission range selector slider thingy on it in the right position for it to start the engine and also for the speedo to work. If this transmission range selector is off even a 1/4" the system wont work. Im going to attempt to dummy the system down.

If you need any help let me know.
 

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Yep i got my factory speedo working. Apparently it gets its signal from the ABS sensors, but somehow requires the transmission control module to do its thing. So basically i have a TCM floating around in the engine compartment; in addition to that i have to have the transmission range selector slider thingy on it in the right position for it to start the engine and also for the speedo to work. If this transmission range selector is off even a 1/4" the system wont work. Im going to attempt to dummy the system down.

If you need any help let me know.
What about the other gauges? Did you have the 6 speed auto stock?

I have a long range plan of converting my 07 V8 Explorer to manual and I expect your range selector trick will be needed.
 

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Discussion Starter #11
The only "gauge" that doesnt work is the tach. I can get it to temporarily work, but things go south with it. My 07 came with the 6r75 transmission. Im still working on getting other things to function. Other members pushed me to buy the ford FSM and its been a major help. Its just gotta find time to sit down and do some hard reading.
 

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My 6R60 and your 6R75 are basically the same thing I guess. It sounds like you'll get the tach down eventually.
 

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Discussion Starter #13
Yea, ill eventually get the tach right. The TCM is inside the tranny, so if you sell your 6r60 to recoup some money you will have to buy a TCM to make things function. Or you could pull the TCM out of your 6r60 but that would probably significantly lower the resale value. I picked up a TCM off of ebay for 200$. I just price checked 6r60 TCMs on ebay any they are kinda salty, might be best to pull your existing TCM and sell the trans without one.
 

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I am working through this problem now on a 04 Sport trac swapped to a 4bt and 47rh. Speedo wont work. Have all the other gauges operational. Have a 04 4.0 manual ranger ECM coming to see if that satisfies all the inputs needed to make the speedo work without hooking up the trans tcm. Thanks for the insight on that though sks72107, did not know the tcm was inside of the trans! thats crazy..

Yep i got my factory speedo working. Apparently it gets its signal from the ABS sensors, but somehow requires the transmission control module to do its thing. So basically i have a TCM floating around in the engine compartment; in addition to that i have to have the transmission range selector slider thingy on it in the right position for it to start the engine and also for the speedo to work. If this transmission range selector is off even a 1/4" the system wont work. Im going to attempt to dummy the system down.

If you need any help let me know.
 

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I am working through this problem now on a 04 Sport trac swapped to a 4bt and 47rh. Speedo wont work. Have all the other gauges operational. Have a 04 4.0 manual ranger ECM coming to see if that satisfies all the inputs needed to make the speedo work without hooking up the trans tcm. Thanks for the insight on that though sks72107, did not know the tcm was inside of the trans! thats crazy..
I have a 01 Sport trac with a Nissan 6 speed, I made a tone ring on the slip yoke to read pulses for the speedo. The factory sensor was on the output shaft on the trans.
 

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Thanks fte, however my 04 ST 4x4 has the speedo sensor in the rear end. Just cant make the wiring happy yet to get the speedometer to work.. Never messed with the factory wiring from the speed sensor to ECM and now it doesnt work so sounds like I am having same issue as SKS72107 was having.
 

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Discussion Starter #17
hope you get it figured out. MY speedo is working just fine now. Im going to relocate the TCM into the center console so its not hanging out in the engine compartment. My tach still isnt working, need to get on that.
 

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Thanks fte, however my 04 ST 4x4 has the speedo sensor in the rear end. Just cant make the wiring happy yet to get the speedometer to work.. Never messed with the factory wiring from the speed sensor to ECM and now it doesnt work so sounds like I am having same issue as SKS72107 was having.
I was told that the speed signal was done at the rear axle so I verified the source before I tore the truck down. That's when I found that it didn't get it from the rear axle (like the Ranger) but from a sensor on the trans output shaft.
 

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Discussion Starter #20
For the most part. Most of the time I'm about 24. Winter time I see a couple mpg drop with extra idle time. I think it still has more efficiency in it. Really hoping to push 26-27 with some tuning.

Sent from my SAMSUNG-SM-G900A using Tapatalk
 
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