Wix Filter/NapaGold Oil Filter vs Pennzoil

• Pennzoil uses a leaf spring rather than a coil spring; the leaf spring must always seat properly onto the end cap. Additionally, a leaf spring can bend under high pressures.
• Pennzoil uses metal end caps rather than the fiberboard end caps.
• The filter media inside the Pennzoil was glued to itself, rather than crimped with a metal bracket.
• Pennzoil uses a phenolic resin which helps to bind the media and protect during high temperatures.
• The center tube of the Pennzoil filter is spiraled for better flow; other brands use a straight tube with spot welds.
• The Pennzoil filter uses a rubber anti-drain back valve. The anti-drain back valve is used to prevent oil from draining back to the crankcase after shutdown. A silicone valve is less likely to break down during high heat than the nitrile rubber.

NOTES:

• We found excessive glue on the end caps.
• The Pennzoil had a low number of pleats compared to the others.
• The Pennzoil had the lowest square inches at 168.