Speed sensor 700R4 transmission
 

During the upgrade to my 54 pick-up I'm installing a 700R4 transmission. The transmission I took out was a 700R4 as well. The problem I have is the old trans had a speed sensor that screwed in replacing the speedo cable, it has worked great for years. The new trans has a electrical/ magnetic speed sensor. the old trans had 3 wires going to the trans, the new trans only takes 2 wires. How do I hook up the old to the new, do I need all 3 wires?

Re: Speed sensor 700R4 transmission
 

If both transmissions are older than 1998 you can just use the tail shaft and sensor from the old transmission. (Both will have the 4 bolt flange) Just move the gear from the output shaft and transfer it also. If the transmission is newer than the it will have the tail shaft with 6 bolts. The do not interchange.

Re: Speed sensor 700R4 transmission
 

700R4's go to about 93 when the 4L60E (electronic) trans came to be.
Is it just a removal of the speed sensor from the old trans and relocating it to the new one, or is it the cable speedo to the electronic speedo?
I have a '89 R4 that had a electronic speedo output, then using an aftermarket cable drive adapter to operate the factory gauge, and an overdrive kick down kit to control the trans (modernizing to only to convert back to old school).

Re: Speed sensor 700R4 transmission
 

these guys have a few info youtubes that may help. a pic of what you had and what you now have may also help.
https://www.monstertransmission.com/...pes_ep_60.html

Re: Speed sensor 700R4 transmission
 

https://www.youtube.com › watch
Quick Tech Tip | Mechanical vs Electrical VSS for a 700R4 Transmission - YouTube

Re: Speed sensor 700R4 transmission
 

it depends on what you had compared to what you have now. some tailshaft housings accept a couple variations, some don't. pics would help.
it would be good to keep your original sensor if possible. the old "one change causes 50 other changes" addage.
ok, maybe I made up the addage, haha

Re: Speed sensor 700R4 transmission
 

the end of this video explains a few different speed sensors that were used and shows what they look like

https://www.youtube.com › watch
700R4 Speedometer Gear | Curt's Corner at Monster Transmission - YouTube

Re: Speed sensor 700R4 transmission
 

I have been watching youtube and doing some research,it seems the best thing to do is get a set of mechanical speedo gears. I watched how to get the mechanical gears changed, looked simple just push down the tab a tap it off. So I pulled the tailshaft to remove the VSS gear, but not so simple looks to be pressed on. there are 2 holes,(I can see one) for the mechanical gear. can I use a puller to get the pressed on gear off?

Re: Speed sensor 700R4 transmission
 

are you able to post a pic or two of the shaft and gear?
if you have the tailshaft housing off it is also a really good time to check the bushing and seal for the driveshaft

Re: Speed sensor 700R4 transmission
 

Got it done, pulling the rear end tomorrow

Re: Speed sensor 700R4 transmission
 

whats up with the rear end? gonna swap it with something else? the whole thing or just the guts?

Re: Speed sensor 700R4 transmission
 

Taking the ford 9" out of my truck so I can send it off to Dutchman's and have it shortened 2.5" on each side

Re: Speed sensor 700R4 transmission
 

Just a side note. My 4x4 version of the 700r4 had only the mechanical gears. There was a guy on ebay who sells these and was very helpful getting the right combination based on wheel size and rear end ratio. Biggest issue were good speedo and replacing all the cable parts.

Re: Speed sensor 700R4 transmission
 

if you need a new cable try an instrumentation shop, they usually have more modern and reliable parts. used to be the go-to when taxi's were cable driven or the big highwway trucks used the cable driven log for speed, down time and time behind the wheel.

Re: Speed sensor 700R4 transmission
 

FWIW i went thru 3 cables and housings before getting a good one. If you buy on line check your return rights/cost before you buy. Heck even NAPA sold me chinese junk.