I use purolater (sp) pure 1 filters in wifes focus and in my expy with mobil-1 oil. Yes I know it is $6 a quart but considering a motor is about $4000.00 to replace what is $24 (focus) or $36 (expy) in the long run. Now we only put on about 10K miles a year on each, so that is only 2 changes a year on average. I am lucky enough to have a company van, to drive to and for work, and wife only puts about 30 miles a day on hers. I am sure Motorcraft is good oil, why would ford recommend something that would make their motors fail???

 

Okay, here's a 100% unquantifiable opinion. My '05 only has about 7K on it, and I had intended to use dino oil up to 10K but for some reason I used synthetic (Mobil 1) on my last oil change. I am now convinced that the engine runs smoother on it, for no reason except that's how it feels to me, especially in the 3K to 4K range.

Now on the other hand, I did cross the 150 hour mark during this period, where some say the computer program changes itself, so who really knows......

 

Oops...I missed that. Sorry...

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Let's see...how can we turn this into a Synth vs. dino thread... hmmmmm...

 

Ok, Motorcraft oil & Air filters ! Has been established !!!!!

Now oils, Mfg. calls for 5w20 oil why 5w30 & what API service Grades. I am a FE man & i know Diesal oils have better oil adtives than car oils. I read the attatchment on post # 13 it was very good . Is there a Diesal 5w 20 or 5w30 oil thay make ????

Don Cross

 

Diesel oils (CC) don't have better additives compared to SI oils, just more of them. Typically.
Never heard of a 5W-20 or 30 diesel oil, only 5W-40.