Muncie 318 trany speedometer gear help!

[Megawatt]

Hi everyon this is my first post.
I have a 65 Chevy c10 pickup with 3 speed on the tree and wanted to know if someone could help me with a question.
My speedometer does not work. I have disconnected and check cable and it's ok
I removed driven gear and found the drive gear inside on tail shaft turns freely with my finger.
I have the long tail shaft non overdrive.
How do I go about to fix this plastic gear. Does the trany need to be removed from truck. Or canI remove the tail shaft
I am not sure what is allowing gear to turn freely. Some sites show a clip that goes with that gear or maybe the gear is broken.
Can't find any rebuild instructions online.
What does it take to repair this plastic speedometer drive gear on output shaft
Thanks, Robbie

[1963c-10]

You can do it with the trans in. Unhook the speedometer cable from the trans tail shaft and you can get access to the speedometer gear. I believe there is one bolt to remove, which will remove the cover and allow you access to the gear. Its an easy fix to swap out the gears. Hopefully the other one comes out fairly easy if its broken. They are plastic, so normally a pair of needlenose plyers will help.

The make them fairly easy to do, as you can correct the speedometer reading off by swapping the gears for different tire sizes.

[1963c-10]

I may even have a spare gear....id check the one you have 1st to see if its damaged.

Also when you checked the cable....did you verify its turning at both ends? It could turn freely and be broken somewhere in the length of it. If speedo is good and cable is good then its fair to think the gear is bad. If that doesn't fix it, then its an internal trans issue. If that turns out to be the case, I have a spare trans that you could come get since were fairly close nc/va....

[Megawatt]

Thanks, but the plastic gear that is free wheeling is the one inside the tail shaft that turns the plastic gear that the speedo cable screws into.
I can put my finger inside the hole and spin the plastic gear that I believe is on the output shaft. This is what I need help repairing.
Thanks again Robbie

[1963c-10]

Im no help there. If it gets to be to big a pain in the ass, come get the spare trans I have sitting here and do a trans swap. I wouldn't put a ton of money into the other trans....unless its cheaper than fuel to come get this one. You might be able to source another trans closer also. But my offer is open if you need it.

[geezer#99]

Leave the tranny in the truck, pull the tailshaft off, slide the gear off the shaft, put your new clip that holds the gear on the shaft in place (the tang fits in the hole in the shaft) and slide the gear back on the shaft over the clip. It should go on only so far.
If you find the old clip in the housing the tang will be missing.

[1963c-10]

Thanks Geezer#99....im no help on internal trans issues.

[Megawatt]

Thanks Geezer#99 for the step by step.
Where online can I get a replacement clip. And gasket
And thanks 1963c-10 If I ever need trany I will check with you

[geezer#99]

TRy these guys. THey might have your parts.
http://www.garagemotorsports.com/muncie.htm

Or these guys.
http://transpartswarehouse.com/

[geezer#99]

One more thing!
Have a big drain pan under it when you pull it apart. One of the bolts that hold the tailshaft on is also the drain for the tranny.

[Ronw435]

If I am not mistaken you will loose the two sets of needle bearinga if you try to remove the tail shaft as the inner gears will come with it. I have not tried to release the bearing from the tail shaft housing and wonder if you could pull it out far enough to get snap ring pliers in to let the housing come off the tail shaft bearing with out loosing the needle bearings. Anyone ever try this?

[frankslagoon]

rons correct. the rear bearing is held in the ext. housing with a snap ring. I don't you can get at it without the mainshaft dropping the bearings. probably just pull the tranny.