Water pumps

Water flow is usually in line with the valve turn thinghy. Whichever pipe the handle is that you pinch is, that is where the water is going to, if installed correctly. If not sure follow pipe back to the pump to determine flow direction.

I found where the noise is coming from . There is a valve behind the hot water tank,in between the hot water outlet and the cold water inlet.
When the valve handle is horizontal ( > ) there is no noise. When the valve is vertical (^ ),I get the noise when the toilet flushes.The water flush flushes either way. My question is which direction should the valve be ,as I don't want to burn out my heating element,if no water flows into the hot water tank.
Thank you for any help

Sounds like toilet water valve is actually the issue.

Pump doesn't know which component is being used...faucet, shower etc

Agree with "it's probably not failing".
If, after following other poster's diagnostic suggestions you still want to replace it, contact ShurFlo and ask them what they recommend. You might get a brand new pump for the cost of shipping, or even free.
They really stand behind their products.

I stuck with Sur Flo when mine died. Slight upgrade but not much.

NOTE: Some multi-switch Sur-Flo installs use a controller unit that is current limited. if you put in a pump that is too big. it can overload and burn out the controller.. Mine is a two switch (SPDT) and does not use a controller.

It sounds like you have a pug of air somewhere in the system. That is the way mine sounds with and air pocket somewhere. purge all the outlets to include the outside shower and see what you have.

Ummm. how does it sound with say the kitchen sink?

My bet is that your pump is OK.

That could be an air leak on the suction side or a plugged up suction strainer.

Symptoms are ,all of a sudden we are getting this ungodly noise when, we go to flush the toilet. You step on the flush pedal and sounds like the pump is going to come apart.

Curious has to what symptoms 'giving up the ghost' means?

What is wrong with your pump....

Did you think about rebuilding your pump? The are super simple. Often cleaning is all that is needed.