Speedometer Needle
 

My speedometer needle has been bouncing like mad. I was thinking it could be loose where it plugs in down below, but haven't really gotten the chance to take a look. Car is a 1990 GT with the 5speed in it. I was hoping for a bit of advice before I start messing with stuff cause I live in an apt. complex and gotta be kinda sneaky when I try and fix stuff. Also, I am swapping to 275/40/17 in the rear and was wondering which speedometer gear I'll need to change to in order to keep my speedo fairly accurate.

Is it making noise too? Could be in need of a new speedo cable or maybe just a couple of drops of oil or graphite down the old one.. My 90 would bounce and make a slight squeak when it was cold outside until it warmed up.

my buddy just bought an '88 GT and it does that, down by like 25mph it bounces all over the place, the guy that sold the car to him said it needed a new speedo cable (since they're mechanical i can understand this.)

I'm guessing its probably the cable on mine then. It makes no noise, and just bounces like mad at any speed.

I had this issue with my 85 SVO and it was the speedo cable. If you know how a brake cable from a bicycle works its the same except in the speedo the cable spins around instead of going in and out.