I recently noticed that my miata is leaking large amounts of oil from the lower end of my motor. I'm new to the miatas and I am curious as to if its a common problem with these vehicles. Also I have an issue with my speedometer and I have pulled the piece out of my trans that sences the speed and translates that onto my speedo. I need to know if it's easy to replace the internal workings because when I pulled the piece out a ,majority of the teeth are stripped. If someone could give me some info asap it will be greatly appreciated.

 

Oil in front? Front crank seal, cam seals, or long A/C bracket bolt is loose (rare).
Oil in back? Rear main seal, cam angle sensor.

Is your crankshaft pulley wobbling when the engine is running? That can make the front crank seal leak.