jedelen, Hi! I've done three cylinder remove/replaces. Basically, with the trailer lowered, a tarp on the ground/cement--take several pictures of pulley placement, locking bar and guide rod placement, etc. I then blue taped the Front Lower cable "FL" same for Rear Lower "RL". Your piston should be almost fully retracted. I use a plastic wire tie(zip tie, medium duty to tie the cables as tight around the pulleys as I can, remove the bolt and washer and again zip tie them out of the way, try to keep SOME tension on them. CAUTION: the locking bar is not held in with any fasteners, it MAY fall after the next step. Ask me how I know. There is a taper type pin on the guide rod-remove that pin SAVE IT! Slide the guide rod to the street side until the curb side falls out. Once free of the HUGE plate, put the pin back in. Using two open end wrenches, remove the locking nut , then the retainer nut from the piston end. AGAIN CAUTION! the Heavy plate will come down (FAST) upon removal from the piston rod end! AND that locking bar!
Next- street side, This area is not the easy end because of space and ingenuity is needed. Carefully remove the "B" nut on the hydraulic line, cap it or use a zip lock bag to prevent contamination. Keep it out of the way without kinking it. Remove the plastic vent line and allow it to drain into a container. ALSO remove that stainless adapter where the "B" nut was attached. On the piston end, remove the cotter pin, nut, washer and then with what ever safe method you can, remove the large pin and the piston should come free. Safely remove it from the trailer.
When you have it repacked ensure you let then know that it is filled with Dextron 1 thru 6 Automatic transmission fluid-- not a hydraulic fluid. Should be bench tested to 2600 psi.
My preferred shop caps and tapes the piston mounting areas, sand blasts it with 220 grit, re-builds it, tests it to 2600psi then primes and paints it gray. Re-install in reverse order. When you raise it, only go about 3-6" several times to get any trapped air out. Then raise and adjust cables if necessary.
I assure you it's not hard, just makes your brain work (or get soft). Take your time, you'll see how it needs to be done.
Best of luck, let us know how you make out.
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