Speedometer cable not working

[k51977blazer]

I have a 1976 k5 blazer turbo 350, speedometer does not work I checked the cable and have movement my cable was connected to this part I never saw before I disconnected that part and connected the speedometer cable directly to the transmission still have no movement any one have any ideas or what that part is called

 

[Bent77]

Spicer speedometer correction. Clean it up, there should be a stamped number on it.
Mine has a .20 correction, makes the speedo 20% faster than it really is

 

[Bent77]

The gear inside the th350 maybe stripped

hook that mess back up to the cable and slowly speed it up with a drill to test everything else in the system

 

[k51977blazer]

Spicer speedometer correction. Clean it up, there should be a stamped number on it.
Mine has a .20 correction, makes the speedo 20% faster than it really is

The cable part that comes out it just falls out is it supposed to

 

[Bent77]

Not usually!

Take it apart, its already broke

 

[k51977blazer]

The cable part that comes out it just falls out is it supposed to

Ok cool I checked the speedometer cable and the speedometer moves with a drill attached

 

[k51977blazer]

I’m guessing the gear is stripped

 

[Bent77]

Cool, you're half way through trouble shooting!

and since your truck is a "K" model, the speedometer is in the transfer case. Unless you have the random 2wd Blazer

 

[k51977blazer]

No I have the 4x4 I’ll have to remove it tommorow
and see I’m sure someone makes the kit thanks for the help

 

[k51977blazer]

Any ideas where I can the spicer speedometer correction

 

[Bent77]

Any ideas where I can the spicer speedometer correction

Did you take it apart and see what was in there?

try that as a google search, that magic widget will show up

 

[k51977blazer]

Not yet I’ll take it apart tommorow and take a picture

 

[sweetk30]

these little plastic drive adapters can fall off . mine didnt work for years until i found mine was missing and now its works as it should .

https://www.ebay.com/itm/GM-Cars-Sp...419165?hash=item4d27c0a81d:g:jmUAAOSwbYZXUL48

 

[k51977blazer]

Ok here’s what i got when I pulled off the rest of everything

 

[k51977blazer]

I put everything back together made sure it seated and tried again still doesn’t work

 

[Bent77]

I put everything back together made sure it seated and tried again still doesn’t work

Did you see the post by @sweetk30 above?

Either the gear inside the output is stripped, or maybe the end of the Speedo cable is no longer square

 

[k51977blazer]

Yeah I saw it I don’t have that plastic piece at all the cable still looks square

 

[k51977blazer]

these little plastic drive adapters can fall off . mine didnt work for years until i found mine was missing and now its works as it should .

https://www.ebay.com/itm/GM-Cars-Sp...419165?hash=item4d27c0a81d:g:jmUAAOSwbYZXUL48

Where does the plastic piece go

 

[k51977blazer]

Ordered the plastic piece I believe that’s my problem thanks everyone

 

[sweetk30]

if you have a ratio box and then cable there is the plastic adapter sleeve like i linked to make the round -tab go to the square drive for the cable .

i ran my truck for years with no speedo until i found this missing part was all that was needed . .

i have also seen a few drive gears with stripped out square inside them . you need a new / used one then and match it to the letter stamped on the side of the body .

this part here . right side you see the 4 flats crimped in to it . inside they can go round and not drive the speedo cable.