Bumping this thread with a new video on 700R4 and 4L60E Forward Drum Repair...The most common pattern failure, by far, is the 3-4 clutch pack burning up...The primary reason for this in my view, is leaks developing at the base of the input shaft where it's pressed into the drum...Over time, milage, stresses and other factors combine to weaken the drum to the point it's no longer making a perfect seal at the 2-3 feed circuit and fluid begins to leak into the case under high pressures when it should be going directly to the 3rd clutch piston to apply and hold the 3-4 clutch pack...When this starts happening, 3-4 clutch failure isn't far behind.
I show a potential repair procedure using Loctite retaining compound, that if ultimately proves itself to work under operating temperatures, will be a viable option for those looking to repair drum assemblies with mild to moderate leaking in lieu of replacing the drum.
