One of my friends ran into rear main seal problems last year. Had 2 new ones leak. He said the black fel pro are made in china now? I decided to use the tan colored Fluoroelastomer in mine this year to be safe.

Doesn't leak. (thank god)

67 Barracuda street/bracket car 11.27-119
68 Dart 502 BB 8.70s-152
414 cid SB Dragster 7.65-174