Search results

  1. C

    Super Tech 20w-50 in my 500,000 mi. Jeep 4.0.Bad?

    My 89 Cherokee has 508,000 miles with mostly Castrol 20w-50 used. The last few years have been the Super Tech 20w-50 at 3000 to 5000 change intervals. Do you guys think im harming the old mill and does the ST have the Zinc that my motor needs?
Back
Top Bottom