REAR MAIN PAIN
We are still getting lots of calls on rear main seal leaks on LS engines after rebuilds. We suggest engine builders install the rear seal with the lip facing the crankshaft, like all other engines, regardless of installation instructions. This change in seal production started around 2007 when the 6.2l and 5.3l LC9s came out and most of the aftermarket followed the GM engineering prints and design.
Tim Schwanke
Schwanke Engines, LLC
Springfield, MN
May, 2018