Odd ABS question: what type of signal?

[Lil'John]

Okay, this is not your usual ABS question This would be for a full float rear axle(95+??)

Can anyone tell me what type of signal the rear ABS signal send out? Pulses per rev or pulses per mile would be a GREAT help.

Back story for the question:
I've retro fitted a full float rear axle into my FJ55. I knocked 7" off the short side to retain stock WMS of the FJ55.

My FJ55 is getting a 6.0L Vortec shortly and I've been trying to figure out the VSS situation since I am using an NV4500 with Toyota tcase. I've got two or three other ideas I'm looking at.

But while putting the axle in, I noticed those nice ABS sensors and thought those would be a perfect way to get a signal to the PCM at a low cost(aka freeish)

[RavenTai]

counted a hub I have here, the rear abs ring has 48 teeth, so 48 cycles per revolution, the training manual says the sensors produce a low level AC voltage, one cycle (low peak, high peak) per tooth

[hj60]

It's nearly a square wave.
So is the VSS.
Problem is the frequency per revolution will be very different.
Also, if you try to use both WSSs therell be frequency overlap (like a flanger for a guitar) that'll confuse the PCM.
You could probably run one of thos VSS correction boxes for bigger tires and fool the PCM into thinking a single WSS is the VSS.
A lot easier than installing a VSS in the stock transfer.
Or, you could just get an 80 series transfer. It'd already have a VSS.

[Lil'John]

Raven, thanks for the tooth count. In my "rush" to get the axle in and together, I forgot to count them.

I wish I could do the FJ80 tcase but no adapter for NP203 that I know of

I would definitely only use one of the signals.

On the difference of frequency, the PCM can be programmed for a surprisingly wide array of inputs

My current other options right now are:

• Use the sender for my new electric speedometer. Unfortunately, the claim is 8k pulses per mile(MUCH less than the 100k normally seen )
• Adapt an aftermarket VSS to work with the toyota tcase.
• Adapt a 40 tooth reluctor ring and Chevy sensor to the toyota tcase (leaning this method right now) Would require larger hole in reluctor ring and hacking up tcase tailhousing

[tblume]

Uh, Houston, we have a problem.........

some of you guys are way too smart for us puny earthlings

oh yeah, where're the pictures of this beast of a '55?

[Lil'John]

I have this habit of out smarting myself

Here is a picture of the pig as I got it:


I've got a build up thread here with LOTS of non-complete pictures in it. About 100 and change posts... mostly me rambling with pictures.
http://forum.ih8mud.com/fj55-iron-pi...-build-up.html

FJ80 axle high lights:

• Post 28 shows the axle as I got it. Fire victim so LOTS of work done to it
• Posts 42 and 43 show the shortened FJ80 axle getting spring pads.
• Posts 100, 101, and 102 are where I do the FJ80 rear axle swap (no axle shafts yet and I'm waiting for hub tool to tighten it all up... also waiting on brake lines/ebrake setup)