My buddy has an old 71 1 ton dodge. The 727 has a problem. When you go from drive to reverse it binds up. If you go from drive to park back to reverse , its fine. Any idea, he thinks its in the valve body.

thanks!

I would suspect a linkage problem, crawl under the truck and observe the linkage as someone sits in the cab and shifts it through all of the gears; look for lost motion from worn or missing plastic bushings in the linkage.

If the linkage is tight disconnect the linkage from the transmission lever and shift it by hand; check for looseness in the lever between detents.

Well maybe I dident explain it well enough. Its going into gear when this "binding" happends but it seems like there's a ton of weight behind it. Like all of a sudden you hooked onto a big trailer.

Sounds like the rear clutch might not be releasing correctly when going from drive to reverse. I would check the shifter linkage.