Which to use with the Federal Mogul steel gaskets to fix the standard intake coolant leak?
Permatex has
Ultra Black Black the Right Stuff Ultra Grey The Right Stuff for Imports
All I can see differenent is the durometer of the cured material. What would be better stiffer or softer???
Should I bite the GM dealership to get the factory sealant? None od the two GM part numbers cross to any of the Permatex line.