Speedometer not working

[Justin84k10]

I have recently replaced my speedometer cable and tested it with a drill and it still doesn't work. Where the cable screws into the t-case is that piece replaceable?

[Captain Swampy]

transmissioncenter.net might have it.  If you're spinning the cable and nothing happens, the problem is between there and the speedometer head. Maybe the cable isn't engaged in the head. Take out the speedometer and spin it.

[Justin84k10]

I think it's something in the t-case because the speedometer spins when I put a drill on the end but when the truck moves it does not.

[Captkaos]

Is there anything broken in the Tcase?

[Justin84k10]

That's what I am thinking because the cable and speedo itself work fine. Not sure what's invokved though with the components in the t-case though?

[Captain Swampy]

It plugs in to a gear that is driven right off the output shaft. You can remove the retainer and the gear will come out. You may need a new o-ring. You'll be able to see into the case thru that hole. I'm assuming you have a 208 tcase.

[Justin84k10]

Ok thank you! I will take a pic when I am working on it tonight. Not sure what t-case I have.

[george]

The plastic gear on the output shaft is likely spinning freely on the shaft.
There is a screw that goes through the gear into the shaft to secure it in on position.
Have the same problem but will not get to it until snows are gone.
A mechanic suggested a larger screw if required.

Must remove tail cone to access it.

[rich weyand]

On a K truck, there is usually a ratio adapter on the t-case.  There is an adapter pin that goes onto the end of the speedometer cable to connect it into the ratio adapter.  If you pulled the cable from the top and lubed it and put it back, that little adapter is sitting down in there and needs to be put back on the cable.

[george]

On my '81 C1500 the little square box on the outside of the transmission was not working.
The transmission shop replaced it with a plastic pin with the appropriate gear on the end - to get the speedometer accurate to within 3-5 mph.
Could this be a similar problem?

[Justin84k10]

I took the piece out of the t-case and everything looked in tacked, the plastic gear was in thier and intact, and the cable is hooked up and everything should work and I'm not sure why it doesn't work.

[rich weyand]

Was there a ratio adapter on the transfer case?