Hi this is Bob. I was a rebuilder years ago, until the Chemicals got to me. But, the foundation of our 4R70W's is basic to the old FIOD, if I recall, came out in 1978. They were cable shifted. Only difference is our years are Electronic. Check each Valve in the Valve Body, with a small Screwdriver, gently moving each Valve to see if they are moving freely. AND, watch out for the Shift Solenoids!! They may look good, but I would WASH them out with Solvent, and use Compressed Air to blow through the openings, and then Test them with 12 Volts to listen for a CLICKING sound. They should have a SOLID CLICKING, not a faint sound. Many don't realize that Solenoids get Clogged, and they will not perform if debris gets in them. Now, if the Tranny has burnt fluid, you may need Clutch Steels. But, if the Steels are slightly burnt, you may use Sandpaper to smooth them. But, if they are 'HOT Spotted' new Steels are needed. Also very important is, checking all the Bushings for wear. They are a soft metal with oil grooves. where all the lubrication flows through. I would recommend renting a Bushing Driver Set, and a Seal Installation Kit. And when assembling the unit, have the tale shaft end DOWN, and the Front Pump side up. As you Assemble, be SURE that every separate piece that goes in, properly BOTTOMS OUT, flat as you go. So, make sure there is Grease holding the washers in place, so they don't fall out during installation. Last but not least, when installing the Torque Converter on the Pump Shaft, be sure to go Straight into the Pump, and SPIN it in place making sure the Converter seats all the way. I tried to make this short, but it grew into this. I'm sorry. I want to make sure all goes well with the Rebuild. BOB.