well the one thing about those ecco smart alarms i've found is you have to be particular where you mount them. Putting them under the floor plate or in any enclosed area causes them to not work properly. They tend to be erratic with the variable noise level detection and tend to want to work at full db level all the time or vary because of the noise echo they detect from being in that enclosed area.
They are sensitive to sound so you would want to mount them in an open area not pointing towards any barriers or noisy components like the engine.
Generally they are used mounted inside the counterweight pointing outwards away from the truck.