Using diff "vss" as an engine vss sensor, is it possible?

Lil'John

Lil'John

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Title kind of states it.

To expand, I've got a Dana 60 from a 2000 Ford E350 van. The stock diff has a tone ring and some sort of a sensor for it.

Can I use this to feed a LSx? If I recall right, LSx likes a 40 spline reluctor ring.

What about a TBI engine? I forget if TBI likes 2 or 4. Is there a converter available?

Lastly, is the ring part of the diff or is it a ring under the ring gear? I haven't pulled it apart yet so this might be real obvious.
 
So we've got two people who don't have a clue if the tone ring/sensor on the diff can be used as an engine VSS. Cool. Do I need to provide a picture?
 
No it won’t work.

also lsx are 24 and 58x depending on the year
 
Twankie said:
No it won’t work.

also lsx are 24 and 58x depending on the year
Click to expand...
I believe you are thinking about crank sensor. I don't think the reluctor ring in a transmission is 24 or 58.

Here is the diff sensor on top:
DSC_0399.JPG

Here is ring gear tone ring:
DSC_0401.JPG
 
If you reprogram the tooth count to work with the ecm (efi live) you are basicaly the same situation as a output vss on a tcase.
 
total newb said:
If you reprogram the tooth count to work with the ecm (efi live) you are basicaly the same situation as a output vss on a tcase.
Click to expand...

I'm using a Land Cruiser transfercase on my project so no 'readily' available VSS at the tcase ;) The "readily" available options are not something I care for. One required a stub speedo cable adapter to the sensor. Last time I tried that route, it was a fawking disaster.
 
Why was it a disaster? When I installed a Atlas II in my 1994 Explorer I needed a VSS so I just had a new speedo cable built with one built into the cable about 10" from the transfer case end where the electrical plugs were located. It works as well as the OEM VSS did.
 
Are you wanting the vss for cruise control or something else?

the pcm doesn’t require it to work if it’s not needed
 
BDK said:
Why was it a disaster? When I installed a Atlas II in my 1994 Explorer I needed a VSS so I just had a new speedo cable built with one built into the cable about 10" from the transfer case end where the electrical plugs were located. It works as well as the OEM VSS did.
Click to expand...
Two fold issues. I dealt with a very shitty company that jerked me around on the part so I ended up with a two piece VSS like you are describing. The stubby cable blew out twice. It was discovered the VSS was the issue and couldn't be warrantied by shitty company.

Since then, I have no desire to use aftermarket VSS like Jag That Run, etc.

I had an output housing fabbed to use stock Chevy VSS(cost cheaper than aftermarket VSS):
split_vss.jpg


Twankie said:
Are you wanting the vss for cruise control or something else?

the pcm doesn’t require it to work if it’s not needed
Click to expand...

My understanding is the TBI PCM requires a VSS for off-idle and at stop idle issues. I don't have the year TBI I'm going to be using but it is a 454 TBI.
 
Did you ever get this figured out? The Sterling 10.25 I have has the same tone ring and plug so I'm curious to know if it could be use for a speedometer in place of the VSS in the transfer case. MY gut says it would if I found a programmer like LT1Swap who was familiar with the Ford rear axle and what the output voltage is.
 
In theory the axle ring could be used. Find the tooth count that makes the engine happy and do the math on the gear ratio to make the appropriate tooth count. The ring is removable so have one cut out that is similar thickness and OD to have the appropriate tooth count.
there are variables that need attention. Is the gm speed sensor 2 wire or 3? The ford sensor is normally 2 wire. Theres a possibility that you could mount a different sensor in the hole with some ingenuity if the gm is 3 wire.

Think outside the box and decide if the gain is worth the work.
 
RunningProblem said:
Did you ever get this figured out? The Sterling 10.25 I have has the same tone ring and plug so I'm curious to know if it could be use for a speedometer in place of the VSS in the transfer case. MY gut says it would if I found a programmer like LT1Swap who was familiar with the Ford rear axle and what the output voltage is.
Click to expand...
The below reply does answer some of my questions.

If I were doing an LS type swap where I could use HP tuner, this would be a trivial solution. They offer a method to convert pulses in to correct "range".

I'm not sure I've heard of an easy method to convert a signal with a TBI computer.

Swampee said:
In theory the axle ring could be used. Find the tooth count that makes the engine happy and do the math on the gear ratio to make the appropriate tooth count. The ring is removable so have one cut out that is similar thickness and OD to have the appropriate tooth count.
there are variables that need attention. Is the gm speed sensor 2 wire or 3? The ford sensor is normally 2 wire. Theres a possibility that you could mount a different sensor in the hole with some ingenuity if the gm is 3 wire.

Think outside the box and decide if the gain is worth the work.
Click to expand...
If the ring is removable, what is different in the diff? Are the gears a different thickness? Or is the carrier different?

It has been many years since I played with a "TBI" VSS... but the LS ones are 2 wire.
 
The only thing different in the diff would be the tooth count. Say you have 4.10 gears. The factory vss reads X number of teeth I'm not sure but we will call it 10 teeth for easy numbers. The driveshaft rotates 4.1 times for every single rotation of the axle. So you would need more teeth on the axle ring than the case output.
If the factory gm is 2 wire then I see no issues there. I was just planning for potential hiccups in the system.
so find the stock gm tone ring count and count the axle ring with the gear ratio in mind and figure out how many teeth you need to make the tbi enjoy what's going on.

Maybe you get really lucky and it's a divisible number based on the two and only have to pull the carrier and grind off every other tooth or something similar. This will all depend on the numbers.
Do a little homework and report back.
1- gm tooth count for VSS
2- ford ring tooth count
3- gear ratio you will run
 
Use pulses per mile as the common denominator. That's what the computer wants to know, it doesn't care if you use the trans, tcase, rear diff, or glue a magnet to a tire.

I vaguely remember that the F350 PSOM wants to see 8000/mi. https://www.fullsizebronco.com/threads/ditching-the-psom-ideas.505822/

The 10.25 tone ring presses (taps on w a deadblow) on the OD of the carrier, with a tab to prevent slipping. Waterjet or lasering a ring to replace it would be pretty easy, as long as you're precise- clearance to the pickup is important (FSB link above talks about .1mm/.004" location accuracy). Also, note the offset- it's not a flat plate, it has a rib on the upper face in the photo so that the teeth are stepped away from the ring gear.

10.25tonering.jpg
10.25tonering2.jpg
 
Yes. We're looking at the face the gear will sit on. I'd feel pretty comfortable cutting the tab off and forgetting it, too. The ring is a pretty tight hammer-fit, and it's just a reluctor, it's not driving anything...






Hmmm, just ran across this. Not totally relevant to yours, but it's interesting.

https://solomotorsports.com/shop/parts/ford-parts/drivetrain/bw1356-vss-relocation-kit/
BW1356 VSS Relocation Kit

The Vehicle Speed Sensor (VSS) Relocation Kit is designed for Ford Broncos with E4OD transmissions paired with the BW1356 transfer case. This is needed when upgrading your stock 8.8 rear end to a stronger axle, like the Currie 9″, since the stock location of the VSS is on top of the rear axle. This relocation kit utilizes your stock tone-ring sensor, which is relocated to the rear of your transfer case.

The supplied VSS tone ring has magnets to signal your stock sensor, which conveys the pulse to your vehicle’s ECU. Without the vehicle speed information being present at the ECU, the transmission won’t shift properly.
Click to expand...
VSS-Relocation-Kit-Ford-Bronco-F-150-3.jpg
 
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