VC3.1 500 upgrade. Rear bed z drops when unpowered.

I just upgraded my machine from 3.0 to 3.1 and after the upgrade the rear Z won't seem to hold the bed in place when unpowered. I'm assuming this has something to do with the new bi-material coupler but I have yet to find a way to 'tension' the connection so that it doesn't drop 40mm. Any thoughts/solutions for this issue?