SUV will shut off at any speed

Welcome to 2CarPros.

I feel you are on the right track with the sensor. Although a new sensor did worse, it may be bad. Here is what I need you to check.

You will need a live data scanner to do this. When the engine stalls and will not start, using the scanner, see if there is an RPM signal. If there is no signal, try a different sensor.

If you have no access to a scanner, when it won't start, you will need to check for spark to the plugs. Here is a link that explains how that is done:

https://www.2carpros.com/articles/how-to-test-an-ignition-system

Here is a link that explains common symptoms related to a failing crankshaft position sensor. See if it seems to mirror what you are experiencing.

https://www.2carpros.com/articles/symptoms-of-a-bad-crankshaft-sensor

Also, when it is running, does the check engine light stay on? If so, have you scanned for diagnostic trouble codes?

Let me know.

Joe