When replacing the knock sensor in a GMC Truck will there be need to replace gasket?

Yes, it's highly recommended to replace the knock sensor gasket when replacing the knock sensor in a GMC truck. The gasket creates a seal to prevent leaks and ensure accurate sensor readings. Reusing an old gasket can lead to leaks, which will affect the sensor's performance and potentially damage the engine. The gasket is relatively inexpensive, and replacing it is a small part of the overall job.