727/Bolt On Yoke Speedo help...

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Hi! I'm Jeff, and I am a recovering MOPAR addict. Well, sort of.

I am currently rebuilding a 1975 Jeep DJ-5D, which has the AMC 232 motor and a variant of the 727 behind it. The guts are the same up until the output shaft. Then, it has a very short shaft, a different bearing set-up (actually held in with a snap-ring in the tail extension), and then the bolt-on yoke. I've heard rumors that this was sort of common for certain truck variants, but I am no expert on that front.
Trans_Is_Complete.jpg


I've rebuilt everything inside the transmission except for the speedometer gear portion. I cannot seem to find the correct part numbers for any of these pieces, so I decided that in addition to prayer for Divine Intervention, I'd ask my Chrysler friends about this.

Here's a picture of what I have now:
727_Speedo_Cable_End.jpg


There's a screw-on connector that goes to the speedometer, which is standard. The cable itself is a clip-in variety. The portion that goes into the transmission is 1 7/8" long, and there's three sections to it. First oil seal is half an inch from the stop, then there's a groove another half inch in for the snap ring, and then there's 7/8" until the exposed cable end.

The black housing/adapter has a seal around it, although mine is hard like Bakelite. The unit has only two ranges on it - 26-31 and 32-38. It is 1 1/2 inches deep.

Then comes a snap-ring that fits over the driven gear. Finally, the gear itself. This one (in the picture) says "37" on it but nothing more. The piece, from nose to tail, is only 1 1/2" long.

It's different than the parts for the 904 transmission - they use a red housing adapter and two clips to hold their driven gear in place. And that's where I get stuck.

All of the parts manuals talk about "long gears" and "short gears" but this one seems to be neither of them. None of my local transmission part houses (in the North Dallas Area) have anybody who knows the 727 well enough to figure out what these are. They certainly are not the standard metal screw-on housing and the long gear that's used in the standard tail extension housing.

So, has anybody out there seen these parts before? Maybe they're standard and I just don't understand how to read the parts catalogs (extremely possible)? Or maybe they are really old and I have to find replacements out there, somewhere?

At the end of the day, I need a new cable, a new gear (I am working on the correct number of teeth), and a good set of seals for the whole package, so that I don't start dripping fluid as I drive.

Thanks in advance for all of your kind help!
 
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Didn't your rebuild kit come with both of those o-rings?

Let's just say that the rebuild kit was missing a LOT of things that I thought would be standard. Yes, it had Kolene steels and red frictions, but the inner piston seals were not present. And the spacer for the second clutch pack - that wasn't there. And the thrust washers/spacers? And a set of springs and rollers for the sprag? Yeah - all extra from the rebuild kit.

If you have a better (more complete) kit in mind for next time, share and I will gladly use it! :thumbsup:

Still, the gear is chewed up and the cable has duct tape holding the jacket together, so replacement is still the best route for those parts.
 
I just use the basic seal, gasket and ring kit and buy the rest separately. About 25 bucks and they have those seals.
 
So, your gear in the second pic resembles the '65 and earlier speedo gears, which are in limited supply. I would send that pic to A&A Transmission, they are Torqueflite experts. The cable would be AMC specific I suspect. The Jeep CJ's are getting more rare as time goes by, but I would think a good CJ parts supplier would have the seals and cable. Is it a 37 tooth gear? There's a DJ group on Facebook.
 
Look at the 727 transmission from a motor home chassis, it uses a bolt on rear yoke. I have no idea if the speedometer pinion will work.
 
So, your gear in the second pic resembles the '65 and earlier speedo gears, which are in limited supply.

That's the sort of info I was needing! I now can focus on old parts, not ones from the 1970s. FWIW: With the 3.08 rear axle I have, and the 205/70R15 tires, I calculate that I'll need a 30.5 gear, so it'll either have to be a 30 or 31.

There's a DJ group on Facebook.

Yup, I know. I'm very active there, but hard core Chrysler knowledge there is hard to come by. They suggest I go to a MOPAR forum. Since I'm a Dart/Duster/Valiant guy, that's how I drifted on down to the A Body group!

Thanks again for the pointers - now I can go barking up a (hopefully) right tree.
 
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