Seized shock

Yes...at least I think that is the deal.
My rear passenger Rancho adjustable shock seems to be locked up. I’ve never had a shock do this, very odd. I push on the rear bumper and the driver’s side dampens up and down but the passenger side is rock hard. I don’t see any oil coming from it, it’s way sketchy driving down the road though. Has this happened to anyone before? Am I on the right track? I have relatively newish rear springs from General Spring as well.
I’m calling Rancho tomorrow to get a replacement seeing as they have a lifetime warranty.

 

It is odd but I have seen it happen. Hydraulic failure I believe.