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Discussion Starter #1
I've been running my Moates tuned '79 Bronco with Ford 400 engine for about 5 years, but one of things I never did when I converted it to EFI was figure out the VSS. I'm thinking of adding it to my truck, but not sure of which vehicle's VSS will be a drop in replacement for the OEM speedo cable.

I dropped a 4R70W into a classic Mustang of mine recently and discovered that the speedo cable and VSS from a '93 5.0 Mustang w/auto drops right in. I'm guessing something like this exists for the 4x4 C6.
 

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The speedo cable and VSS plug into the transfer case - so, what TC are you running? What are you trying to accomplish exactly?
 

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alot of vehicles had a cable driven VSS had the electronic input for cruise control info. for example my 88 Bronco with C6 had a the cable driven VSS which also told the ECM the speed for its cruise control. same with the 87 Bronco AOD I working on, my 90 F250 AOD had it.

Just remember that the rear axle VSS/ABS sensor reads much differently than the cable driven VSS. so if the tune your using got its readings from the rear axle, it will read very differently than the cable driven VSS. have I tried to interchange them and the rear axle ABS would read 120mph when the VSS was at 20MPH. you can change the pulse-to-speed ratio (or whatever it would be called) with the tuner if you can figure out the math to do it.
 

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Discussion Starter #4
My TC is an NP205, mated to a C6. The engine is EEC-IV controlled, but I've turned the VSS input to the computer off since I don't have one installed. If I did, I'd have better throttle control at low RPM offroad while crawling because the EEC controls dashpot and other stuff with VSS feedback (if enabled).

My rear axle is the stock Ford 9" 31-spline unit, so drum brakes out back and no ABS.
 

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If your computer is set-up for VSS on the rear axle, I don't see why you couldn't swap in an 8.8 with VSS.

Advance Adapters has a bunch of experience wiht trany and te-case swaps, they may be able to help. Thing is, I don't believe the older C6 nor NP205 use VSS.
 

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Discussion Starter #6
The '86-93 5.0 Mustangs with an AOD transmission all came with a mechanical speedo cable that was driven by a VSS that plugs into the transmission. It was literally a drop in replacement for the speedo cable in my '71 Mustang and works great. I was hoping someone here might know whether a VSS/speedo cable assembly from a late model vehicle might drop right into an older mechnical speedo TC or trans.
 

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consider a GPS speedo with a signal output for the computer? Even if it gets mounted somewhere out of sight.
 

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Discussion Starter #8
Ok, so I believe that Motorcraft DY587 is the VSS that will fit in a '79 Bronco's C6. The speedo cable needed is then from a '93 Bronco.
 

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If your computer is set-up for VSS on the rear axle, I don't see why you couldn't swap in an 8.8 with VSS.

Advance Adapters has a bunch of experience wiht trany and te-case swaps, they may be able to help. Thing is, I don't believe the older C6 nor NP205 use VSS.
I don't think this will matter. I have a 1990 with a 9" rear, original BW 1356 with VSS, and an E4OD all controlled by a 1993-1995 Lightning computer. I don't think the computer cares where the signal comes from.

tim
 

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I agree with the above it just needs to see a signal cross over a certain point to know that vehicle is moving, or coming to a stop
 

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Discussion Starter #11
So this appears to work great on the '78-79 Bronco platform. If you need a VSS for your EEC-IV or EEC-V (or whatever EFI system you have), Motorcraft DY587 does the job. Just swap the stock driven gear onto the DY587 and use a speedo cable from a '93 Bronco and you're done.

Also, my mistake for stating that the VSS goes into the C6... it's into the NP205!
 
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