Replacing CM871 crankshaft damper

[Waterloo]

You will need that seal tool to do it properly. I think, from my bad memory, run around $300 for that tool... If high miles on the truck, may as well replace it, especially with everything tore apart. If you are removing those front covers, they have those o-ring style gaskets. If you for some reason pull those covers, replace those o-ring style gaskets and save yourself a headache, been there, done that.