I don't know about the 'synthetic caused an engine tick' but I know that if you have an oil leak, no matter how small, synthetic will make it worse. Synthetic is so 'slippery' that it flows easily through the smallest of spaces. A minor oil leak can become a major leak overnight with a switch to synthetic.

I'd advise against synthetic in any engine that has existing oil leaks.

1995 Trooper S
5 Speed
Bone Stock, for now...
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It's better to regret something you did
Than something you didn't do
--Michael Balzary