Jinma Backhoe cylinder

Try heating up the cylinder on the outside of the threaded area. This should cause it to expand and maybe it will release its grip on the threads of the gland end. Also try tapping around the outer side of the threaded area with a hammer. Like an impact wrench to “jar” things loose.

Depending on the style and quality of your spanner wrench, a cheater pipe for more torque may be required. Be careful with that though.

Good luck

I can rebuild your rams if you want to send them to me.  I can do it in about 1/2 hour, and seal kits are $25.  So right around $75 total.