Change the master and reservoir out.
If that doesn't work change the slave.
You want a specific answer to a question that has no answer.
Hydraulic clutch system works fine on, literally, millions of Rangers without any problems.
Out of those millions there are going to be problems with any mechanical system, and while it is not common it is to be expected with those kinds of numbers(systems in use).
Rangers clutch systems do have a specific issue when you bleed it, because of the angle of the master, so there are many posts about this, but it is a knowledge issue, once you know how to do it it is no longer an issue.
And out of the millions of clutches replaced over the years the posts about bleeding are few in that respect.
So you have that knowledge and have tried it, it didn't work, so you have a parts problem.
If your new master has a warranty then take it back and exchange it.
If not then see if you can find OEM parts, 3rd party "can" be OK, but OEM "will" be OK
Last edited by RonD; 01-22-2016 at 10:40 AM.