Generally it’s pretty simple to know if they were low pressure or high pressure gas charged. I’m new to the scene so never have experienced new ECS shocks but am interested in rebuilding mine if possible. If they were gas pressurized from the factory, they would have shaft retention clips on the shock shaft that when removed would either quickly extend the shaft, or slowly. If they didn’t extend at all (or were very slow) chances are they weren’t gas charged. It is possible to low pressurize a shock utilizing nitrogen gas bags made specifically for shock use and that’d be the route i’d take if I was rebuilding regardless if they were pressurized from the factory or no.
If they had 150 psi as some have indicated, you’d know taking it apart as that’s pretty significant pressure. you’d hear it for sure when you released the seals… it’d rocket the shaft across the room if you didn’t restrain the shaft… very dangerous.
One thing I’ve noticed is there is no mention anywhere in the tech manuals, service manuals or marketing materials that the struts are gas pressurized units. Considering the minutiae of what they do describe for the vehicle, it seems that it’s a glaring omission if they were indeed pressurized.
I’m following this with great interest and appreciate the work your doing.