After my recent encounter with the law ticket post
I've decided I need to know how fast I am going.

This happened a while back, but when it stopped workin I think the speedo started buzzing and the needle went all of the way around and hasn't worked since.

What would that mean? Do I need a new gauge, or has something else failed?

Used gauges are cheap enough, probably cheaper than repairing the old one. North Hollywood ..... Speedometer (?) and Palo Alto speedo are companies that probably could repair/restore your gauge.

So it sounds like it's the gauge itself.

I am looking at a used set if I need it.

You can check it quickly by removing it from the car and using a hand drill (in reverse) to spin the mechanism. If the needle doesn't move then you could open it up and see what the damage is.

Orr buy a cheapo gps unit

GPS on your phone or download a a speedo app?
I've got 3 speedo's you can pick from. $50 each shipped. They all work but I can't guarantee how accurate they are. Also if you aren't running stock tire sizes, the speedo will be off a %.

if it is the cable, be careful the speedo cables come in differnt lengths. make sure you order the right one.

ask me how i know

it could also be the speedo angle drive. i have had two break on me so far. And i cant remember the last time i had a working speedo

If the odometer works, the angle drive and cable are fine.
The trip odometer is separate and frequently fails all by itself, but if it's working, the angle drive and the cable are fine.

Odometer not working either.

I was hoping that the speed o' meter going all the way around then failing would point to a specific cause.

Guess I'll have to do some investegating.

IIRC Performance Products/Automotion & maybe some others sell replacement gears for inside the speedo, if it's bad & if you want to try to rebuild/replace yourself.

You can do it cheap, you can do it right, but you can't do it cheap and right. In this case, it's not likely to be the usual odo drive gears, and taking it apart is gonna be waste of time, IMO. Buying a used one is gonna just postpone the inevitable. I suggest you just have it fixed.

The Cap'n

good advice