Volvo vhd steering box was pushing oil out end off shaft where steering wheel linkage bolts on hard to steer losing

Hello and thank you for using Just Answer. My name is ***** ***** I'd like to try and help. On your issue there is a few things that I would do, Once you replaced the gear box make sure it was bled out properly. This is done usually by jacking up the front suspension and turning lock to lock several times. This will help to make sure the air is all out of the system. I would check the front suspension components and make sure there is nothing that is tied up. This will put a lot of effort on the gear box and will cause an over pressure issue. I would also check the pressure out of the pump as this has an internal valve that can stick open or close. Also check to see if this has an aux assist gear box on the pass side. These can cause this type of concern as well. I hope this helps. Thank you