Quote from an eddyzima post in moving2's recently closed thread on Mobil 1 noise:
"When i put M1 in my 2500hd and it ticked(warm idle) i called mobil's 800 number. the fellow told me it does make some engines a little noisey, but your engine is being protected. that was in 2005 so i am sure that was sl oil."
It seems to me that if a Mobil representative answering its 800 phone number inquiries says that Mobil 1 makes some engines a little noisy, that goes a long way toward proving that its a FACT that Mobil 1 makes some engines noisy. I find it hard to believe that Mobil would let the rep say that if it were not true.
I'm not a Mobil 1 basher. In fact, I'm on my second 10,000 mile run of Mobil 1 in my 03 Ford Ranger, and in my wife's 03 Subaru Forester I'm on a 10,000 mile run of Mobil 1 EP, after a 10,000 mile run with Mobil 1. Neither engine has been noisier with the Mobil 1 or Mobil 1 EP. I'm pretty much sold on Mobil 1 and Mobil 1 EP.
However, during the 46 years that I've been driving, anytime anyone had a noise develop in their engine it was considered to be something to be concerned about, checked into, and remedied. So if Mobil 1 makes some engines noisy, I don't blame them if the owners switch to another oil. I'd switch too.