Just recently bought the truck(1988 1500 5.7) and everything seemed to check out. Took a 150 mile trip and when I arrived, the truck won't shift from first until about 30mph. The fluid does look burnt. A lot of shops are wanting to just immediately skip to replacing the trans and as a broke college student that will not be fun. A lot of reading stated that a vac line goes to the rear of the trans to the manifold that could be clogged? Also, is it worth getting a flush, filter, fluid change or does it sound like the problem will be more severe and I shouldn't bother wasting the time and money? If I was home, I could do the filter and fluid myself. Any responses and help would be appreciated! Thanks!