THANK YOU! I had a stuck piston on the same jack model. I used a vice grip to rotate the head of the stuck piston and then it came out. I cleaned both pistons well and lubed them with jack oil and now it's good as new!
This helped a ton thank you! Same issue - looked like metal shavings from the coating jamming things up. I have the 2 1/2 ton and it was 5mm allen (not T-25) to remove the retaining bar btw.
I have the 3 ton version of this with the right side piston sticking, even after cleaning and lubing it was still sticking so I took the whole piston and bore out and it goes in smooth half way down then immediately stops. Currently looking around to see if anyone sells replacements.
I'm next to it, not behind it. Right hand is holding phone, left hand using jack. Vehicle is 4000 pounds and this is the front where the engine is. 350 cubic in v8. And lastly you are probably just a manly beast.