Mobil 1 vs Amsoil

[thesource]

I use Advance Auto Parts house brand oil and a Ford Motorcraft filter every 4K and have never had a single issue either. In fact, most of the time, other than the oil looking slightly darker, it still looks pretty damn good when I change it.

In my wires car, I use Ford Motorcraft oil and filter every 5K and basically the same thing. The oil looks slightly darker but still very clean and probably good for another 5K if I wanted to push it.

[J&T's 82]

The only problem I have ever had from oil was from the old 80's Penzoil. I had to have a set of heads on a 305 vatted several times due to the paraffin. These days I use what ever the oil change place or the dealer puts in it. I have been driving cars for 25 years and have never had an engine problem due to oil.

[white trash wagon]

Agreed with the above, I have a Ranger with 150k miles, all of them with Walmart 5W20 oil every 4K miles. Doesn't leak or burn a drop - still gets 27 MPG.

I'd only run a synthetic if I had a turbo, or supercharged car.

[mikeb]

Motor oils have improved tremendously over the stuff you used to buy in a round can back in the day. And with the changeover from carbs to FI, and tighter tolerances in engines, and higher running temps - most any oil will give satisfactory service life nowadays.

I've run ordinary pennzoil 200,000+ miles with no issue. Done the same with mobil 1. I've used walmart conventional oil & synthetic oils with good results. I've run the gamut of filters from frams (ugh), motorcraft, mobil 1, k&n, a/c, purolator, and even supertechs and have never had 1 single issue.

I'd say the conventional oils are good for 5k miles and synthetics a bit longer. I think that comparing oils for ordinary passenger car use is almost splitting hairs. Use what you are happy with, and change it as often as you think you should, and you'll be fine.

[4bangen]

I run motocraft in mine because it's the cheapest semi synthetic I've found. 217k on my last mark vii, and 207k miles on the one I have now. Both cars easily passed state inspection every time and never smoked, leaked or broke. With the exception of a water pump on the 89 I have now. I ran mobil 1 in my tbird because of the turbo heat and driving it 100 miles a day, but like stated above, with n/a cars I go cheap.