speedo gear question

[tttuba]

I have a 47 GMC with the stock engine and trans and my speedo is not working. Cable is good and speedo is new so figure must be the gear in the trans. Any ideas? Any other possibilities? I disconnected the cable and turns freely. If connected to the speedo and I turn the other end of the cable it registers on the speedo so must be in the trans somewhere?

[JumboAMONGus]

try a new plastic gear , ive never had one go out , not sure but mine is starting to act up and the cable i pulled out and its all good and the speedo turns free also , but going at around 20 or more it starts sounding like a bind and it stops

[1project2many]

With replacement cables, cable core length is sometimes a problem. So is having the core installed backward (the small ring crimped to the core should be at the top). Original trannies had metal gears and they lasted forever. If you have a plastic gear it may be worn in the center. It's easy to remove and inspect on most transmissions.

[tttuba]

So I have never removed one and actually had my son get under the truck to remove the cable. He fit under there better than me. Can you tell me how to remove the gear once the cable is removed? And if I need a new one where can I get one?
btw. ring is at the top. That I know

[1project2many]

Look for a bolt holding a clip holding a sleeve. Remove everything to get to the gear. Replacement gear source depends on trans type. Google is your friend!

[mr48chev]

One thing I used to see was from the result of cables binding up and that was that the square hole in the gear that the cable goes into getting rounded out.

If you got the whole cable and housing as a unit you should be ok but if you just bought a replacement cable and cut it to fit it may not be long enough as 1project2many mentioned.

[tttuba]

I bought the truck this way and cable was disconnected. I bought a new speedo. Cable looked new so I thought maybe disconnected due to bad speedo.
Now when I hooked up new speedo still nothing. So going to have to figure out how to get gear out.

[oldcouple]

Look here http://chevy.oldcarmanualproject.com...4247csm432.htm

[tttuba]

So took the cable off the trans, took the plug off the trans and looks like the gear inside BUT it doesn't come out. So thought I would jack up the back end and turn the rear wheel and have son under the truck to see if the shaft on the gear turned. It does so doesn't look like the gear. So now I had him place the cable on without the plug and shaft turns but cable doesn't. Looked at end of cable and looks good but still doesn't work. So I am thinking wrong cable. It looks new but maybe someone bought the wrong one.

[oldcouple]

try pulling it out of the housing, my 57, both ends looked fine, pulled it out of housing, it was broken in the middle. you can get the whole thing or just the cable. Or just take the trans end out and chuck it in a drill and watch the speedo. Whiiiiiiirrrr. lol.

[1project2many]

^^^^

If the speedo is stuck or the grease is dried out it doesn't take long for a new cable to snap. Help / Dorman sells a cable core that's cut to length.

[tttuba]

If I take the cable entirely off....it spins ok one way but tight the other way.Will try pulling the cable out of the case and see what it loos like.

[tttuba]

Originally Posted by 1project2many

^^^^

If the speedo is stuck or the grease is dried out it doesn't take long for a new cable to snap. Help / Dorman sells a cable core that's cut to length.

any idea what the dorman part number is?

[1project2many]

http://www.google.com/search?hl=en&s...1c.EpCPtQ4NtMI

http://www.dormanproducts.com/c-644-...ter-parts.aspx