1968 camaro all original with cruise control, power glide transmission, the speedometer stopped working, the cable doesn't turn at all, to rule out the cruise servo im just running the cable from the transmission, i pulled out the gear at the transmission and a few teeth are worn its a 19 teeth gear, my question is could it be that simple?

Im thinking that there are 2 gears right a driven and a drive gear? is it possible to replace the other at the drive shaft without droppining the transmission or should i simply wait and replace the 19 piece gear first to see if that fixes the problem?

 

It depends on how badly the teeth on the driven gear are chewed up. It's also quite possible the drive gear on the output shaft may have slid back. There is a flat spring clip that holds it in place, and they can break over time. You can remove the speedo gear housing from the tail of the trans, and look in the hole. If you can't see the gear straight back in there, then it slid back. To get to the gear, you need to remove the driveshaft, then remove the tail housing. The transmission stays in the car.

 

i replaced the speedo gear today and now it works again however from 0-30 mph the speedometer fluctuates crazy back and forth once it hit 30 mph and it above it works great what could be wrong? Im thinking the speedometer itself could have gone bad ..

 

Have you messed with the cable? If not, yank it out of the casing, clean it well with brake cleaner, and lightly lube it up with a graphite based speedo cable lube. Also while you have the cable in your hands, check for any kinks, bends, or frays.

 

cables are brand new tied 3 cables does the same on all 3 i think its the speedometer only does it from 0-30mph after that it works flawlessly ...

 

If it doesn't bother you, then leave it. Unless you want to start taking your cluster apart. If my memory (what's left of it) serves me correctly, the mechanism inside the speedo that drives the needle is a centrifugal weight inside a round drum. It could be all gummed up inside.

 

stopped working this morning the new sppedo gear got chewed up im not convinced both the drive and driven gears need to be replaced. In the power glide the gear is metal, a shop told me they would have to heat it up to pop it off, they said they could use a platic 1, futhurmore i noticed when backing up it almost soundd like a wind up car so something is going on, the tail sfahet will have to be undone to get to it about 65 in labor.

 

There is a gear in the back of the speedo as well if it were me i would check it just cause the cluster is not hard to remove and worth taking a look anyways also this little gear is needed to be changed for different gear ratios to fix to correct speed reading. don't know if it would break the cable or not though.i have 4-speed muncie i'm not sure about power glide info sorry