Just talked with a1. Who did the trans I guess it’s what happens when it’s been sitting too long. The converter drains back. It’s works fine after I drive it every day
Convertor drainback is one of the FREE FEATURES of the 727 ... You original question says it feels spongy AFTER it warms up ? That didn't make it sound like convertor drainback. Chrysler FINALLY did something to help combat this in the 48RE trans after mid 2003 I believe it was , they added a seat ring to the stator support and more seal surface in the convertor snout for the seal ring to seal against.
Anywho it takes roughly a minute, to a minute and a half, for the entire hyd. system in the trans to charge and the convertor to refill , I assume your trans has the upgrade manual valve , but anyway pop it into neutral after starting and sit for a couple minutes before trying to engage drive.
