My speedometer goes all the way to 110 - 140 while im going 20 -35 is the gauge bad or would it be the speedo gear?

 

It's most likely the guage. It works by a magnet that is close to the indicator and it pulls against the spring. If it starts rubbing, it will pull up and then release. If it has been sitting for a long time, it may free up. If you've been driving it regularly, it probably will not.

 

Usually. if it is your speedo, you'll hear a spinny kind of noise coming from the dash. You'll find at a complete stop, like a red light, your needle will still be dropping as if your still slowing down. You'll also notice while your gaining speed that the needle is twitchy, like it isn't sure if your going 35, 34, 35, 36. Eventually it will just quit working, but as it gets worse the noise will increase.
Hope that helped.

 

speedo .. not the gear.. wait for it to die then replace it