Sounds to me like you better find the relief valves and get them set right. I run a similar set up on my splitter. Just with a single instead of a double spool for the lifts then through the power beyond port to the splitter ram. Both valves have pressure reliefs, both needed set right. My first valve is set to 2900psi (lift) and second (ram) is set at 2800psi. I was told I couldnt have the first valve set lower then the second valve relief pressure. My ram valve also has auto return function wich has really no affect on system pressure as it's set to kick out at 300 psi on return stroke. I was having a bit of a hard time assessing your plumbing but it should go some thing like this, pump out to lift/wedge valve, out the power beyond fitting to the ram valve. Both the ram valve and first valve should have returns hooked back up to the tank. If that's all hooked up, system max pressure will be set off first valve and ram pressure set off second valve. There shouldnt be anything wrong with your pump If it hit 4k psi and didnt blow anything up. It's a relief issue or valve issue. The muck is a separate issue and very irritating, but easy enough to deal with.