got the car running sounding shifting correctly and in proper timing. I dropped the instument cluster 20 minutes at most pulled cable form both the cluster as well as the trans mission both are intact and square and when inserted into the cluster the needle would move as fast as i would turn it.
transmission end all was intact and when i turned the cable with my finger from top end it would turn fine. The speedometer is not reading any speed, and definitely cant drive it without. what could it be?

 

plastic drive gear in the trans itself might be shot, thats the only other link

 

is that a hard fix? what does it entail?

 

If that is the case you need to pull the tail shaft if I remember correctly and replace it

 

interested in thread so just leaving somthing so i can see any replys/ updates) my 87 firebird automatic, speedometer is jumping like crazy. Chilten manual seeming pretty useless here. VSS looking a 100 dollars i dont have, so opening cluster up to try and look in there and try and clean or inspect cable.

 

You have a vss unit so no cable leads to trans just wiring , but i have heard of folks swapping out the vss for the mechanical cable.