When Do I Start Using High Mileage Oil In My Car or Truck?

<p>Why does my 2004 Suburban Transmission slip? How can I fix it?<br /> Why does my Ford Flex have Gas Pedal Lag? it's not safe.<br /> Why does my GMC go into 4x4 Low by itself?<br /> My Subaru has a banana in the tailpipe or at least it feels that way.<br /> When do I start using High Mileage Engine Oil and what is it?<br /> Why does my Chevy Scottsdale 454 Transmission slip?<br /> Why does my 2011 Ford F150 Trans slip?<br /> Lots of slipping transmission here. When was the last time you serviced your transmission? </p>