Burnt oil

2005 JEEP GRAND CHEROKEE
162,000 MILES • 4.7L • V8 • 2WD • AUTOMATIC
Avatar
DANNY MARTINEZ2
  • MEMBER
  • 6 POSTS
My SUV keeps burning oil but there is no leak any where and no smoke coming from the exhaust. already took it to a shop so it can be raised to look deeper but no leaks. can anyone help?
Aug 8, 2017 at 10:39 PM
Advertisement
Avatar
CARADIODOC
  • CERTIFIED EXPERT
  • 34,306 POSTS
You can add a small bottle of dark purple dye to the oil, then check a day or two later with a black light. The dye will show up as a bright yellow stain that you can follow back to the source. If the engine is burning the oil, the dye will show up inside the tail pipe. Auto parts stores will have the dye for the fluid being checked. Those that rent or borrow tools should have a black light.
Aug 9, 2017 at 3:48 AM
Avatar
STEVE W.
  • CERTIFIED EXPERT
  • 15,113 POSTS
The 4.7s are known for bad PCV valves and valve stem seal failure causing them to burn oil. The PCV sticks open and the vacuum sucks in oil. The valve stem seals split and oil is drawn past them into the combustion chamber.

Easiest way to see if you're burning oil is to pull the plugs and see what they look like.
Aug 9, 2017 at 11:28 PM
Advertisement