almost every time i get goin past 85-90 my speedo will make a strange grinding sound and sway anywhere between 20 to 120 mph. once i start to slow down it goes away. i asked my dad and he said that its pretty normal for that to happen when its worn out. If so, could i get some directions on how to fix or replace?

 

Sounds like your speedo cable might need to be lubed. Take the dash apart to gain access to where the cable screws into the cluster. This will get you access to the cable itself. You should then be able to spray some lubricant down the cable. Don't use WD-40 though. Use a graphite based lubricant. That is where I would start anyway.