700r4 speedo question .....

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uprdn84

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Jesus I'm all over this forum asking stupid questions. Why does my speedo cable plug look different than the plug on my tranny? It won't fit. and how can i fix it? Hotrodpc is probably gonna nail me on this.......damn. lol..
 

HotRodPC

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So you're saying you have a Speedo Cable, but your transmission has an electrical plug in??? If this is true, then you have a mechanical speedo cable, which you should have in an 84, but someone has installed a later model 700r4 from a 90-93 transmission that uses an electronic speedometer and/or Vehicle Speed Sensor (VSS) with a reluctor wheel on the output shaft instead of a plastic speedo drive gear.
 

MrMarty51

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So you're saying you have a Speedo Cable, but your transmission has an electrical plug in??? If this is true, then you have a mechanical speedo cable, which you should have in an 84, but someone has installed a later model 700r4 from a 90-93 transmission that uses an electronic speedometer and/or Vehicle Speed Sensor (VSS) with a reluctor wheel on the output shaft instead of a plastic speedo drive gear.
HHHHMMMMmmmm,do I see another TBI conversion a coming ?????:happy175::popcorn:
 

HotRodPC

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Or just change to an electronic speedo cluster from a 90-91.
 

supercharged

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I ran into the same issue, I pulled the T350 and installed the 700r4 .
The 700 has electronic pickup and t350 is mechanical, was gonna swap tale housing ,but it was a different length ( shorter I believe ) so we would of had to swap output shaft too.
We thought it was a good idea to just stick with the electronic speedo since there is so many variables in actual speed,gear changes tire sizes etc.
I was told if we change the speedo to electronic we could calibrate it a lot easier.
Makes sense if this is true.
 

uprdn84

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So can i just change out the vss to a gear drive?
 

HotRodPC

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To change to gear driven, you'd have to pull the trans, and swap out output shafts on the trans too. So yes, it can be done.

And true if ou got all that was needed to do the electonic speedo, they can be calibrated for gear swaps, tire size swaps etc and keep the speedo accurate.
 

MrMarty51

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And it makes a good "Platform" to start Your,to TBI swap.:naughty:
 

bucket

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To change to gear driven, you'd have to pull the trans, and swap out output shafts on the trans too. So yes, it can be done.

And true if ou got all that was needed to do the electonic speedo, they can be calibrated for gear swaps, tire size swaps etc and keep the speedo accurate.

I thought you could just pull the ring off the shaft and install a speedo gear on a 700r4?
 

HotRodPC

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I thought you could just pull the ring off the shaft and install a speedo gear on a 700r4?

I know you can swap the gears, BUT, isn't the reluctor built into the output shaft? Don't get me to lying now. It would be great if it was that easy.

Now the 4x4 units, it doesn't matter, and come to think of it, now that I mention 4x4, I think you're right bucket, it's the Tcase output shafts that can't be changed right??? :shrug: Hell, I'm not positive now. Let's research that and find out fo sho. We might come up with some good news.
 

HotRodPC

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You can, I did it. It's a pain in the ass though.

What do you mean a PITA? Just remove Dshaft and tailshaft housing right? Or do you need a pulled to get the reluctor off?
 

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