The 400 Source brown Viton rear seals fixed my leak up boogie
I had used two other new black seals with no luck on this motor whiney
I do use a sealer, Permatex adhesive sealant only, on the sides of the seal holder to seal the holder to the block on both sides towards the crankshaft flange and the bottom also by using a thin putty knife to try and force the sealer into the cracks between the block and seal holder bottom also wrench up
I change the seal holder also twice so I may have had multiple problems, not just the defective seals confused
IHTHs thumbs

Mr.Cab Racing and winning with Mopars since 1964. (Old F--t, Huh)