I went to a genuine O-Ring shop for my retract problem. I let him do the work without any micro-managing him. He tried a few rings and they didn't seem to fit, because the aluminum part was too wide for one ring. He pulled out what is called a "backup" ring that is split Teflon and goes behind the rubber o-ring. This is to snug up the O-ring so it cannot deform under pressure. I put them in the retracts and BAM, they worked like GANGBUSTERS!!!!! POW!!!. Man, troubles OVER! I'll list the specs here in case you want to try some. It doesn't seem to matter which side of the O-Ring you put the backup ring on, as air pressure is applied from either direction. I installed mine with the BU Ring towards the main gear strut with the O-Ring towards the outside. It was a bit tough on one cylinder getting the O-Ring back in the tube, but it went in, finally. Tore a bit of the ring off (very very small slivers), but didn't matter in the actual system test.
I bought some Silicone shock oil for RC trucks, 45 weight, and used that for assembly. I added a bit of silicone grease on the threaded end to help seal. Boom that was it. Case closed! I haven't checked the system yet for any other leaks, but consider this a real good day.
Backup Ring #111, Teflon
O-Ring 10mm x 3mm Buna
Pic here. I forgot to take a pic of the assembly, but it's not rocket science.
