I just replaced the oil in my 2004 Jeep Wrangler today - I thought I'd give synthetic oil a try because there was a "Mobile 1 oil and Bosch filter" deal at my local auto shop.
Until now I have always used off-brand regular oil and FRAM filters, which have done their job just fine.
After putting the synthetic oil in my jeep the engine seems runs noticeably quieter than it did before. Is this because of some property of synthetic oil that I don't know about? And even though I do have very good hearing I am open to the idea that this is just my imagination.