I left said gasket off my 3800 HO72 axle on one side but kept i on the other. The side with the gasket suffered a hub-seal failure and I noticed oil leaking onto the outside of the alloy wheel through the decorative/cooling holes. I pulled it all apart and the reason for the gasket quickly became apparent. There are holes in the hub that line up with holes in the drum. These holes had ducted the oil to the outside of the drum where it runs through a little channel to the inside of the wheel. Without the gasket, it would have leaked into the brake assembly ruining the shoes.
I fixed the leak and pulled the other side apart and installed a home-made gasket. Some axles have a sheet-metal dish under the wheel cylinders that will catch and duct any leaking brake fluid out through a hole in the backing plate; not HO52/72 axles unfortunately.
I agree this assessment is correct. I am searching for the OEM gasket and I guess I will have to make one. I don't have section 6.819 in my parts book either. Anyone know the part number to fit the rear drum on my 66 K 20?
