I have used mobil 1 on every car i have owned and have had nothing but good luck
1992 Oldsmobile cutlass supreme = sold at 195,000 miles, still running strong without any issues
2001 Focus SE Sport = sold at 145,000 miles, still running strong without any issues
2005 Saleen focus = sold at 120,000 miles, still running strong without any issues
2013 Focus ST = Running Mobil 1 currently and dont plan on switching
Is Mobil 1 the best oil available? probably not, Amsoil and Royal purple may be better but i dont know. But cost per performance wise its a great oil. Every mechanic friend i know uses Mobil 1 in his personal car and tells me to use it as well. Every mechanic also tells me to stay away from Penzoil products. Are they bad? i dont know ive heard of buildup issues from it but i personally dont know for sure.
What i do know is that mobil 1 is a good oil and obviously doesn't ruin engines due to my own experience. And i was never nice to any of my cars. I took care of them, but i ran several of them very VERY hard.
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