I've been running a walbro for about three years now and its making some odd noises. like an oscilating pitch instead of the steady high pitch whine.

car doesn't feel any different but I'm just wonder what the normal life of these things are so i can prevent something bad from happening.

 

Like most electrical devices, they go when they go, I wouldn't say they have a specific lifespan. I would have a look at your fuel pressure when it's making weird noises and see if it's ok, other than that check the fuel pump pickup and filter sock in the tank and make sure it's not pinched or clogged etc.