G-Tech external drive with Thunderbolt 2 randomly disconnects

MacReverb wrote:

I have a 4G G-Tech drive with a Thunderbolt 2 connection connected to my MacBook Pro using a Thunderbolt 2 to Thunderbolt 3 connector that is used only for time machine backups. After 4 years of reliable service, the drive now disconnects constantly. While it appears to reconnect and remount, once the disconnect occurs, the drive becomes unusable. I have tried a new adaptor, new cable and every port on the MacBook. I have also tried running it through a CalDigit 3 Plus but without success. I have another G-Raid drive from G-Tech connected to the same machine using firewire 800 connecting through a firewire to thunderbolt 2 and thunderbolt 2 to thunderbolt 3 adaptors and it works fine. I was about to start ordering another external drive but have read other threads on this forum suggestion this issue could be a design flaw in both thunderbolt 2 and 3. Anyone have any insights into this issue and possible solutions? Much appreciated.

Buy a new drive more compatible with your available ports and compare the results...

It sounds like your old TimeMachine disk is operating in a state of failure and will continue to fail with increasing frequency, in this case replace the drive.