• Register Today It's free! This box and some ads will disappear once registered!

question about 96 & 98 5.0 VSS/OSS


Kingfish999

New Member
Joined
March 8, 2015
Messages
19
Reaction score
0
City, State
Florida
Year, Model & Trim Level
90 F250 w/ Explorer 5.0
im doing a Explorer 5.0 engine/tranny/efi swap in a 90 F250 I have as a project. it is all out of a 98 Explorer but due to the PATS, I used a 96 PCM. I have pretty much everything done and the engine runs great and the truck moves but I cant figure out how to get the PCM to read the vehicles speed. without it im stuck in 1st gear.

the tranny has the OSS on it. according to my EVTMs, the 96 PCM uses the OSS to control the tranny...

96%20T1_zpscesdvwyk.gif


but then I see this that shows the VSS and doesn't seem to control the tranny. it shows it going to the same harness as the tranny (C116 connector). I would think if it was going to the rear axles VSS, it would go through the C115 and show it going through numerous other connectors getting there

96%20E4_zps7hb9ldry.gif


the 98 seems to use the OSS also...

98%20t3_zpsxbjvmomr.gif


... but seems to also use the VSS on the rear axle.

98%20t3_zpsxbjvmomr.gif


98%20vss_zpshfb3yclh.gif


I have the OSS hooked up and none of the wiring to it seemed to change between the 2 years. The F250s 10.25" axle has a VSS on it just like the Explorers 8.8" axle. Ive tried wiring to it but nothing seems to work. Do I need to connect on to it and is there a way of not using the ABS module?
 


Join the Elite Explorers for $20 per year. Gets rid of the ads! New $5 per month "try out" option.

Explorer Forum has probably saved you that much already, and will continue to save you money as you learn how to diagnose fix problems yourself and learn which modifications work without having to experiment on your own. Elite Explorer members see no advertisements, no banner ads, no double underlined links, can add their own profile photo, upload photo attachments in all forums, and Media Gallery, create and save more private Conversations, and more. Join Today. Your support is greatly appreciated.




Kingfish999

New Member
Joined
March 8, 2015
Messages
19
Reaction score
0
City, State
Florida
Year, Model & Trim Level
90 F250 w/ Explorer 5.0
darn pics wont show some reason :scratch: is there an issue with posting pics from Supermotors?
 




boominXplorer

Elite Ranger
Elite Explorer
Joined
September 16, 2002
Messages
9,196
Reaction score
656
City, State
Virginia Beach, Va
Year, Model & Trim Level
00 4x4 Mounty
The 98+ uses the rear axle to calibrate speed. 96 and 97 use a vss in the tailshaft of the transmission. You either need to add the pins in the harness or get a 97.5 harness (to match your EGR setup). The 98 harness will not match the 96 computer and some pins are different for the transmission. If you get a 97.5 or earlier harness you will need the plug off the passenger side of the trans for the valve body on the 98, its different.
 




96ex5.0

Elite Explorer
Joined
August 11, 2012
Messages
550
Reaction score
21
City, State
canyon tx
Year, Model & Trim Level
96 explorer 5.0 4x4 5spd
The 98+ uses the rear axle to calibrate speed. 96 and 97 use a vss in the tailshaft of the transmission. You either need to add the pins in the harness or get a 97.5 harness (to match your EGR setup). The 98 harness will not match the 96 computer and some pins are different for the transmission. If you get a 97.5 or earlier harness you will need the plug off the passenger side of the trans for the valve body on the 98, its different.

Yup what he said.
 




Kingfish999

New Member
Joined
March 8, 2015
Messages
19
Reaction score
0
City, State
Florida
Year, Model & Trim Level
90 F250 w/ Explorer 5.0
yes I know the 96 and 98 use different wiring. I have compared the wiring between the 96 and 98 C202 (PCM plug). there's some differences of course but not much differences. the EGR is different but I got a plan for that. I got to add a few pins but there not a concern. the 98 uses a few extra that the 96 doesn't so I wont even bother with them. from what im seeing I don't even have to change anything relating to the tranny or basic engine controls. even the Tranny Range Sensor seems to be the reusable as the 98 TRS has extra pins that will just be ignored cause the 96.

so the 96's VSS is on the back of the tranny but is not the OSS? from the wiring it seems the 96 uses a OSS and VSS but that's seems stupid to have 2 different sensors that give similar data.

I wish I can figure out why my pics wont post. kinda annoying

EDIT: alright I got pics reuploaded somewhere else and there working
 




Kingfish999

New Member
Joined
March 8, 2015
Messages
19
Reaction score
0
City, State
Florida
Year, Model & Trim Level
90 F250 w/ Explorer 5.0
ok I think I understand what I need to do now. i was unaware that they used this VSS on the back of the tranny. i wouldn't think any vehicle would use a VSS that's originally designed for a cable speedometer. it must produce a different signal than the ABS sensor on the rear axle. ill have to try adding it in when i work on it next week
 




SoHK_alumni

Active Member
Joined
July 29, 2014
Messages
463
Reaction score
11
City, State
Tampa, FL
Year, Model & Trim Level
5.0 V8 2002 Ranger
Actually, the ABS system turns the abs signal into exactly the same signal as the VSS.

No matter if it's the earlier VSS, the ABS system or the PCM/OSS system, all three offer the same signal to the rest of the vehicle.

The VSS itself is a bone simple signal generator.

One wire to ground, the other to the grey/black speed signal for the PCM.

If your application needs a speedometer drive cable from the transmission for the speedo, the cruise control's used by Ford of that era used an inline VSS with an pass through cable drive just for the cruise control module, it too will offer the same speed signal as the other systems.
 




Kingfish999

New Member
Joined
March 8, 2015
Messages
19
Reaction score
0
City, State
Florida
Year, Model & Trim Level
90 F250 w/ Explorer 5.0
I don't need a speedometer cable cause I converted my speedometer to use a PSOM used in 92-96 trucks. ive tried the rear axle VSS directly and the PSOM VSS output and neither worked. so my last chance is to use the VSS on the back of the tranny that too me still looks just like the VSS used for cable operated speedos on the old trucks



or does the ABS unit convert the signal? im not using any ABS and have the trucks original RABS bypasses
 




SoHK_alumni

Active Member
Joined
July 29, 2014
Messages
463
Reaction score
11
City, State
Tampa, FL
Year, Model & Trim Level
5.0 V8 2002 Ranger
I'm not familiar with the ABS system on the F150s so I can't say what your ABS does or does not do but your '96 PCM will happily accept the 3000 pulse per mile signal of the transmission mounted VSS. You'll probably need to run a wire from the VSS to the Grey/Black wire that goes into the PCM and a ground wire for the other side of the VSS.

I just hope the later '98 4R70W still has the drive teeth cut into it's output shaft to rotate the VSS's driven gear.
 




Kingfish999

New Member
Joined
March 8, 2015
Messages
19
Reaction score
0
City, State
Florida
Year, Model & Trim Level
90 F250 w/ Explorer 5.0
I just hope the later '98 4R70W still has the drive teeth cut into it's output shaft to rotate the VSS's driven gear.

ya I checked today cause I was wondering the same thing. it does, it just has a plug in the hole. I can feel the gear inside with my finger. now I just need to find a speedometer gear and figue out how many tooth I need. its been while since ive messed with speedometer gears. wish they sold them at auto part stores



as I side note, does anybody on here know where I can get the original 98 PCM sent and get flashed so it gets rid of the PATS and maybe a few other things? I have 2 PCMs for 98 5.0 and it would be nice to have 1 as backup and have the correct wiring harness to it
 




Kingfish999

New Member
Joined
March 8, 2015
Messages
19
Reaction score
0
City, State
Florida
Year, Model & Trim Level
90 F250 w/ Explorer 5.0
so I wired in the gear driven VSS and it seems to respond to it now. I spun the gear by hand and it showed changes in speed on my OBD-II reader. I also did manage to get the rear axle ABS sensor to respond but it gave WAY too high of a signal (showing like 120mph instead of 20). apparently the VSS gear in these 4R70Ws are different then the ones used in the older transmissions because the gear I tried is from an old C6 to test with and it doesn't seem to reach the gear in the 4R70W. I ordered a new gear that should work
 




Kingfish999

New Member
Joined
March 8, 2015
Messages
19
Reaction score
0
City, State
Florida
Year, Model & Trim Level
90 F250 w/ Explorer 5.0
I put my new VSS gear in. it wasn't much different that the one I tried before. also it still didn't seem to work. but now I think the VSS itself is defective as it only sometimes shows when I spin it be hand.

also I think I do need to change the tranny range sensor cause I got a code for it today and it still wouldn't go into another gear .

I also learned something I never expected. with the tranny range sensor unplugged, the PCM seems to default it to being in D as a failsafe. this didn't surprise me. when it did this, it actually started going into other gears. also not surprising. what did surprise me was that the OSS apparently acted as a backup VSS. it wouldn't read any speed till it reached about 30mph and then it was reading almost very accurate. I had the gear driven VSS unplugged at this time so it had to be the OSS.

either way im going to replace the VSS hoping its just defective. then im going to try and find a 96 TRS connector at the junkyard. the new TRS came with the connector but the pins are too different so I need the pins form an old connector
 




Birdy

Active Member
Joined
May 7, 2011
Messages
363
Reaction score
46
City, State
Richland Hills, Texas
Year, Model & Trim Level
1997 5.0 XLT, 96 4.0 ohv
I know this is an old thread, but did you ever get you're transmission shifting correctly?
 




jwrezz

Elite Snow Shoveler
Joined
March 23, 1999
Messages
1,122
Reaction score
7
City, State
Parsippany, NJ
Year, Model & Trim Level
1996 XLT
Another guy digging up an old thread. Just wondering if any one with the gear driven, t-case/trans mounted VSS have found any type of conversion or easy fix for the worn drive gear inside the t-case.
 




MM.4x4.Explorer

Elite Explorer
Joined
June 27, 2014
Messages
24
Reaction score
15
Location
Colorado
City, State
Colorado
Year, Model & Trim Level
1997 Explorer Sport 4X4
I have a 97 sport 4x4 (4.0 ohv) with the 5 speed auto. anyway, is there any way to bypass the vss in the transfer case and use the abs sensor from the rear axle? Then program it for whatever size tires I have/ever decide to put on the truck? (So basically change it from the 97 system with the VSS to the 98+)
 




jwrezz

Elite Snow Shoveler
Joined
March 23, 1999
Messages
1,122
Reaction score
7
City, State
Parsippany, NJ
Year, Model & Trim Level
1996 XLT
That would be too easy! I'm still baffled. I'm happy to see some life in this thread tho.
 




410Fortune

Ice Season
Staff member
Moderator
Joined
August 3, 2000
Messages
26,362
Reaction score
2,032
City, State
NORTH IDAHO, 7B
Year, Model & Trim Level
B2 "Slightly" Modified
Callsign
FOURTEN
No reason to be baffled anymore

YES THERE IS A WAY
Its called the Dakota Digital BT-1000

I have installed a few of them now
You can use the signal from the 8.8 speed sensor, grab it and send it to the dakota box, buffer the signal and send it back to the PCM, GEM, Speedo, cruise control, etc etc and the truck will be happy. With the dakota digital speedo interface in place you can also now adjust your speedometer as you drive via bluetooth to make any small corrections needed for tire size, etc

Check this out, I have detailed the install a few times now, here is one of my writeups
 




jwrezz

Elite Snow Shoveler
Joined
March 23, 1999
Messages
1,122
Reaction score
7
City, State
Parsippany, NJ
Year, Model & Trim Level
1996 XLT
No reason to be baffled anymore

YES THERE IS A WAY
Its called the Dakota Digital BT-1000

I have installed a few of them now
You can use the signal from the 8.8 speed sensor, grab it and send it to the dakota box, buffer the signal and send it back to the PCM, GEM, Speedo, cruise control, etc etc and the truck will be happy. With the dakota digital speedo interface in place you can also now adjust your speedometer as you drive via bluetooth to make any small corrections needed for tire size, etc

Check this out, I have detailed the install a few times now, here is one of my writeups
Thanks! I had looked up dakota digital last year as they had some promising products. Now seems ready for prime time!
 




410Fortune

Ice Season
Staff member
Moderator
Joined
August 3, 2000
Messages
26,362
Reaction score
2,032
City, State
NORTH IDAHO, 7B
Year, Model & Trim Level
B2 "Slightly" Modified
Callsign
FOURTEN
yes somebody just had to get one and figure out how to wire it up in these Fords.... Getting the box is easy, doing the wiring is pretty simple, just have to sort out where to grab the signal and where to send it back properly without messing with ABS brakes.
Then it was all about sorting out the math, knowing what signal you are getting (tone ring on 8.8 has 108 teeth) and what the truck wants to see (Ford speedo's traditionally want to see 8000ppm)
Now I use them all the time to fix speedo issues, can use them for tachometer corrections also
Will work in just about anything from my 97 diesel to wifes 07 cruiser
 


Join the Elite Explorers for $20 per year. Gets rid of the ads! New $5 per month "try out" option.

Explorer Forum has probably saved you that much already, and will continue to save you money as you learn how to diagnose fix problems yourself and learn which modifications work without having to experiment on your own. Elite Explorer members see no advertisements, no banner ads, no double underlined links, can add their own profile photo, upload photo attachments in all forums, and Media Gallery, create and save more private Conversations, and more. Join Today. Your support is greatly appreciated.




Top