Could you provide more info on bolts with nylon inserts. I am aware of such nuts, but never heard of such bolts

I did speak to a very knowledgeable lady in their industrial tech support department. She said that stainless was a difficult material. Said that their 243 blue product(this product is an upgrade from their standard blue 242 product which does a better job in a contaminated environment,,,read oily) had a problem with stainless and that the recently upgraded version has been improved so as to no longer requires primer step before applying 243 or 242. The primer is used to "etch" no n-compat metals so as to allow their products to so their job,,,,somewhat complex system,,,go to their website

Also she told me that locktite should be applied in bolt holes,,,not only on bolts when used in "blind" holes as air that is forced out blows locktite off bolt threads,,,,,somewhat hard to do when engine is in car and you are looking up trying to do this.

I too have arp bolts everywhere in my engine,,,,only the pan is causing issues,,,removing arp's flat washer, replacing with lock washer has helped but no home run

I have now ordered up a super performance gasket and a new set of mr. Gasket steel bolts. Not only are they not stainless, but also have serrations under the head,,,hopefully to help hold in place once torqued,,,although now am somewhat concerned that serrations may distort torque readings.

My experience suggests not to use arp bolts on oil pan,,,in particular with their included washers. Replace with lock or star washers if you insist to use. Locktite in this environment is suspect unless you have a perfectly sanitary bolt hole and bolt,,,and I would still only use 243,,,,hard to find but amazon has it.

Incidentally I did call arp tech support on this. Told the tech that I had torqued to 15 pounds. He axed what size bolts. I said 5 16ths. He said that was my problem, that I should tighten to 24 pounds. No manner my argument about oil pan distortion etc. he was not persuaded and told me that if I did not go 24 pounds that the bolts would always loosen

Draw your own conclusions on arp's official recommendation from their tech