What might the issue be, I replaced the master and slave on my truck at 207k kms(`130k Mi) the slave was weeping a bit, the clutch and everything had previously been replaced by previous owner at 177k. it has 231 on it now what would cause the slave to royally crap the bed. its leaking bad enough that I am lucky to get around the block in it. seems worse if engine is running and I get to a certain point in the pedal travel and it just loses pressure and drops to the floor. so just of 20k on it and the slave is gone again. I have heard weird stories about slave needing to match clutch also needing to match the master. like what the hell. did I just happen to get a crappy one? I believe it was a dorman replacement... should I get an actual ford one? replace clutch and everything again? I really don't feel like getting into this a 3rd time in less than 3 years.
Don't feel like you are the Lone Ranger though, my tale of woe beats yours.
About three and a half years ago, my daughter wrecked my new to me 95 F150 shortbed regular cab 302 M5OD 4x4, three weeks after I bought it, and about four days after I sold the Ranger I had been driving. (Black ice and concrete bridges win against half ton pickups every time). Thankfully we both walked away with no injuries.
Anyway I needed wheels, right now. I bought another 95 Supercab, 300, M5OD 2x4 for transportation. A few weeks later, the clutch hydraulic line quick disconnect disconnected. After towing it home, I started working on it and put in a new clutch and pressure plate; with the master and slave cylinders and line from the wrecked parts truck. I never could get all the air bled from the clutch system.
August of last year I was going to pass the truck to my daughter, but told her it needed tires and a bit of work before I thought it would be safe and dependable enough for her to drive. It sat for two or three weeks before I got tires on it, making it necessary for the clutch to be bled yet again.
When I finally got her outside of the house to help, the bleeder valve broke off.
To make a long story short, she got mad and I finally put in a new slave and the original master cylinder (the one in the truck did not seal when I disconnected the lower end, fluid just ran out the end) this spring and I have been driving the truck ever since.
This slave cylinder that I bought from Oreillys is the first one that I have not had to bleed. It actually works, engaging and releasing like it should.
I have despised hydraulic clutches since the first one I had in a '57 F-100.
You probably just got a crappy slave cylinder. A lot of the hydraulic parts in the aftermarket are made in the Far East and can be of dubious quality. Replace the slave with one that's made in North America (Brazil is also acceptable as they're still cranking out trucks based on the OBS machines down there.)
The master and slave needing to match refers to size - you don't want to change the leverage ratio from stock unless you know what you're doing. For example, fitting a larger master cylinder while keeping the slave the same size can result in clutch overtravel and sundry other fun problems. If you are buying stock sized replacements, this is irrelevant because you're not changing that.