I believe the lip seals they refer to are on the pistons inside the clutch retainers. You really should get this book. It will help you understand the advice you get on this forum. It has in-vehicle tests you can do with compressed air and a troubleshooting section. Based on your symptoms, it could be a ton of things. This book will be the single best investment you make into your transmission at $28.00 https://www.summitracing.com/parts/sad-sa394