your opinion of oils
 

ok Just wondering what you guys would think of these oil comparisons.
I have Castrol GTX
Mobil 1 Synthetic,
Mobil Super 1000,
Quaker state Defy,
Royal Purple High performance Synth.

I have a 1998 Ford 4 cyl, 140 000k on it.
What you think the top 3 oils are for my type of vehicle in this list?

Just run synthetic and the weight you need for your climate unless your vehicle specifies 5W-20. I live in Central Texas so I use 10W-40 although it says 10W30 on the oil cap because it gets very hot here.

i agree with meistreguy .i use quaker state 5w-30 synthetic

Any api certified oil in the correct viscosity should be fine. Best thing I would tell you is pick one you like and fits your finances and run like the wind. Mobil 1 would be my preference, and I'm a longtime valvoline user with never an oil failure issue. Any name brand should do fine, and synthetic even better. I have used about every name brand available over the past 25 years and never lost a vehicle due to the oil not working.