Ill break the VB open but need alternative steps if it goes wrong ,always a backup plan in my case.Some reasearch done and a few steps yet to do till I submitt to the VB being the issue,the b2 piston needs to be checked out ,the things I have checked on about the VB are looking very promissing though , finding someone who warranties the part has been found .Ive inspected the trannie pan for any debree,it has the normal grey thin silt at the very bottom of the pan that Ive always found after these steps of, inspecting ,replacing filter and refilling,nothing out of the ordinary .I hate to open up the B2 piston and all its steps till I get it in a garage,check it then start after the vb..Still hesitant on dropping the valve body for the same reason.Im religious about service on any daily driver Ive owned jn the past ,this at once a yr service.A good T Rebuilder shop has a VB on the shelf,just havent a price yet .All the other surrounding T shops use them on Mercedes Trannies and VB related issues so Ive got some confidence that the VB will be worth it .Ill pay $500 or less ,only if I know for sure its my issue.Im hoping to have them look at mine to save a step first to verify a complete clogged VB and this while I watch to take photos for this post .I can then go to take the new VB for reinstall with a better feeling after spending that kind of cash.Its a 722.315.If it doesnt go as Im hoping I have a good matching working trannie sitting in the wings,just not rebuilt ,Ill put the VB in it and go for the reinstall with some new seals.Still working the problem .