1954 F100 short bed body onto a 1999 Ranger short bed Chassis

[donalds]

Does the GEM talk back and forth to the

Yes because the PCM can access functions of the GEM for testing
In fact all modules can communicate with the PCM

 

[allmyEXes]

So, when tire size changes does the PCM get accessed to change it for the tire size change?
ADDED: reading this. Don't know if it is correct.
Tire size, VSS etc

 

[donalds]

So, when tire size changes does the PCM get accessed to change it for the tire size change?
ADDED: reading this. Don't know if it is correct.

It does with my SCTX4 tuner and it does not have the ability to connect to the GEM The tuning device that is

I never did understand why the GEM monitors speed
Probably 4 wheel drive related..

 

[allmyEXes]

The tudner, LOL

 

[donalds]

The tudner, LOL

I'm not supposed to have beer but I did today

 

[allmyEXes]

I added a link to post #42. It sounds like the GEM module is sending a signal from the VSS to the ABS? I'll have to re-read it a little later. Thanks for your help, wife is calling me. BBL, be back later...

 

[CDW6212R]

The GEM is part of the 4WD circuit, but I didn't know the VSS went to it an not separately to the ABS. So the GEM wiring you cut should have the VSS and ABS wires that were part of the path for the VSS, which has to go through the 98-01 ABS, and then to the electronic speedometer. For a manual cable speedometer, you need the VSS which can be had directly from the trans, the tail shaft sensor you pictured above.

 

[allmyEXes]

OK. For now it looks like I will have to re-install the GEM module to have the Ranger speedometer working again. I just slid up under the Ranger and on the tail shaft housing is a cast place for a VSS or speedometer cable however, even though I could remove the tail shaft housing and open up that hole to use a VSS or cable, without looking at it I don't know if the output shaft is machined for the worm gear to drive a speedometer gear. So I may have to use the Ranger speedo/instrument while it is still 3.0 auto powered. The differential has the VSS plugged in it.
When I convert to the '97 MM and 4R70W is when I will be able to use a cable plugged into the tail housing. I'm not around the Merc at the moment but I bet one of you Dons or Jamie would know from having experience with the 1997 5.0 Explorers if that is the case. I'm not sure how well my chicken scratch drawing is but ultimately with the 5.0 and auto trans I would want to do something along these lines however it will be simpler than I am making it because I'll be using the Holley Terminator Max PCM and parts. ABS may not even be on the final product so I'm not going to complicate it with that. It will have Cruise Control though.

 

[allmyEXes]

@CDW6212R I'm trying to pick this PCM 3.0 FF pinout chart apart 1999 Ranger 3.0 FF PCM pinout post #4(That Jamie fixed me up with a year ago) and see what I do need to operate the engine and trans, AC and all the gauges including speedo. I'm unable to make out the words on pin 1 because of the Photobucket logo. Pin 3 has a TR in the description. Is that trans related? 27,28,29 all transmission related. 34 Flex Fuel Sensor which I do have. 49 and 50 have the TR thing again which I'm not sure about. 53 and 54 two more transmission related items. VSS on pin 58. 64 digital tr sensor? trans again? 79? what is that? 90, 91?? 84 turbine speed sensor? What turbine?
I don't see a pin for speedometer. Is that why I need a GEM module? You think that there would be a pin for that though.
However, all of the transmission related stuff looks like it is controlled entirely by the Powertrain Control Module.
ADDED 11:33 p.m. down at the bottom of the page is a PDF document for 1998 Ranger GEM wiring. I need to use just enough of it to get the speedo working. Not anything else. No wipers, no interior light delay etc
1998 Ranger GEM pdf

 

[410Fortune]

You do not need the gem to get the speedo working
The 98+ ranger vss for the speedo is the rear axle 8.8 sensor, the signal is fed directly to the abs module which does the buffering (changes the pulses per mile down to the 8000 rotations per mile the speedo wants to see) then sends that signal to the gem, cluster, speed control and others.
You can use a Dakota digital or other brand speedo driver to emulate this. You can use any vss on your truck, wheel speed sensor, tailhousing sensor, oss sensor, or 8.8 ringer gear vss sensor, and buffer the signal to get close to the 8000ppm the truck wants to see.


In order to use a cable driven speedo you will need a tailhousing with a vss in it that can accept the cable, any 84-97 truck has this,
In 98 they went away.

Not sure if that helps, but I have done this a few times so if you need something let me know. I have made a 49 f1 body fit a 97 awd sploder, I have also converted countless rbv to other drivetrains and always figured out a way to make the speedo, odo, cruise, abs, 4wd and tach work
My 88 bii used a cable driven speedo for many many years before I finally went electronic aftermarket
There are ways! Aftermarket to the rescue!

 

[CDW6212R]

I don't know what any of those circuits on the chart are for in general, I haven't dug through a pinout chart like that in about 17 years, for my 99. The #1 is a Shift Solenoid, and it looks like a B to me.

 

[CDW6212R]

I wonder if the old aftermarket speedometer calibrating devices can help with the Explorer's speedometer, to adjust the accuracy at least? I have one on my old Mark VII with 3.73 gears, it fixed the speedometer very well. I got that for about $50, and found another one years later for about the same, they were small black boxes with four wires, about 1"x4"x5" or less.

BTW, the output shafts of the 4R70 had the speedometer splines on them through the 90's, up to around 2003. Ford has other applications still using the trans VSS sensor, so they kept making those output shafts until they knew they wouldn't need them, and of course used up what they had.

 

[allmyEXes]

Thank both you guys. I know some of this we covered before. Sometimes I can't remember the solution if I don't do the work right then, after figuring out the first time.
I guess the question now is, if I take the 99 Ranger tail housing off to swap out with a '97, will the groove and little dimple be there on the output shaft to be able to install the hidden worm gear for the mechanical operation?

 

[410Fortune]

My 88 bii was just like that, your sketch
97.5 pcm for the v8
93 explorer transfer case
I used a 97 v8 speed sensor
Vss mounted in the t case tailhousing
The two wires feed the pcm, gem module (if you have one) abs computer, ESOF, speed control, etc.
Pull the w white plastic cap out of the 95-97 style vss and stick your 1988 bronco ii speedometer cable right in there.
Worked great for many years

I finally went to a digital speedo from auto meter and used the wires,’ditched the cable

My 96 explorer I added the vss drive gear to the output shaft of the t case by dremmeling a hole for the check ball and a bb holds the plastic drive wheel in place. This allowed me to use a 95-97 style vss again make the truck happy, easy to add a speedo cable if needed.
With the correct tailhousing you can add the speedo drive wheel

This was all way before the Dakota digital speedo driver module and others
Like it were available, now I just use those lol

 

[CDW6212R]

Thank both you guys. I know some of this we covered before. Sometimes I can't remember the solution if I don't do the work right then, after figuring out the first time.
I guess the question now is, if I take the 99 Ranger tail housing off to swap out with a '97, will the groove and little dimple be there on the output shaft to be able to install the hidden worm gear for the mechanical operation?

I don't know about the V6 transmissions, those for different applications might have had the speedometer splines removed sooner than the 4R70 did.

 

[allmyEXes]

I looked under the '97 Merc and it does have as you all said a VSS stuck in the tail housing of the trans. So it is not going to be a problem hooking up a speedometer on my custom gauge set which the speedo is from a 1970 Mercury Cougar.
I also looked at an output shaft out of a 1990 A4LD and it has the swirl cut on the output shaft instead of a place for a nylon gear. There may not be a way to install a gear on the 1999 trans output shaft. I may have to for now, cram the Ranger instrument up behind the hole for the 1954 instruments. Ugly, but functional.
Post #2 in the link below has a diagram of the VSS path for a 1998. I don't know if it correct for the 1999 Ranger.
`1998 Ranger VSS path

 

[allmyEXes]

Post #49 has a PDF for 1998 GEM wiring. I think most of the colors match up to 1999. I have determined that I need to hook several wires back up.
1st connector numbers 1, 6, 9, 11, 14, 15, 18. 2nd connector 14, 26

Twisted pair light gr/blk and red/pink come from the VSS. I also have the gray/grey with a black stripe between thumb and index finger

 

[410Fortune]

You can add a drive gear even with the swirl! The style
I used simply
Needs a check ball to hold in in place, so if you can dremmel a half hole you can slide in a drive gear

 

[allmyEXes]

@410Fortune It sounds like you used an old C-4 type gear. What did you think about all of the GEM wiring? Have you had a chance to look at the PDF doc?...
I think I have spent enough time on wiring for now.
I was looking back at some of my pictures from last year and I came across these that were never posted here.

A guy somewhere here on the greater internet bought these for his mid-fifties Ford truck project. He painted them before he knew
that they were for a truck a different year than his. They are correct for mine. I bought them cheap enough that I got the paintwork free

Somewhere else here in our great nation, someone is building a truck and has to have "perfect" parts. I purchased these for a reasonable price

Backside. These were purchased last year too. Look ok for 68 years old

 

[410Fortune]

Gem wiring and pdf doc? I have some catching up to do!! Will report back