Originally Posted By: addyguy
When I worked at a WM TLE, we had a Pennzoil sales rep come and talk to us.
Long story short, he was the same as this - no matter what the oil, change it at 3k miles (5k km). He said it is a complete myth that synthetics last longer than conventionals - he said they both get dirty just the same, so they need to be changed to get dirt out of the car. Clamed the ONLY advantage of synthetics was better cold-starting ability for winter, NOT exteneded intervals.
I asked him about longer intervals being specified by manufacturers, and he took the classic line of 'yes, they do, but think about it - they don't want your car to last forever, they want to sell you a new one, don't they?' He basically said that anyone that 'actually cares' about their car will change thier oil at 3k.......
His commission check depends on how much of the [censored] is spewed out and how much people buy into it. I'm guessing his checks are rather huge
Sadly, I think the large majority of the population has the old school mindset that oil should be changed every 3k (less if possible).