When i bought my 2000 mustang i thought i would put synthetic oil in it. It was towed when i bought it to a shop and never ran until after i did the oil change with 5w30 synthetic oil, Wix filter and Sythetic Lucas oil additive. I went chasing noises for months. Timing chains, power steering pump, water pump, idler/tensioner pulleys... each time everything getting a little bit quieter.

I got to the point that i was sure i needed new lash adjusters. The car started to burn oil on startup...

Do 4.6L engines not like synthetic oil?