Mopar Oil Filters Any Good?

jbc426 said

All the above filters bypass a significant amount of oil that doesn't get filtered during normal use. The only filter I know of that doesn't ever bypass any oil is from Jomar.

Jomar filters saved my bottom end from damage with I blew out all the needle bearings in my T&D rockers due to improper valve train geometry.

This damage happened over time, and I never found an intact needle bearing in the pan. There were parts of them in the heads. It was strange, and took Dwayne Porter to figure out what caused it. None of the debris made it back into the bottom end. That's the Jomar 100% No Bypass difference.

Click to expand...

I was under the impression that the only time oil bi passed any filter is if it was clogged or there was a restriction.

As found when researching filter operation....



The oil filter bypass valve opens when the pressure across the oil filter exceeds a certain threshold. This happens when the oil filter gets clogged and can no longer allow oil to pass through efficiently. A clogged oil filter restricts the flow of oil, which causes a buildup of pressure behind the filter. This pressure triggers the valve to open and allows oil to bypass the filter entirely and flow directly into the engine. It ensures that the engine still receives lubrication, albeit without filtration. This is a temporary solution until the filter can be replaced. The valve will close again once the pressure normalizes, and the oil starts flowing properly through the filter again.

The bypass valve is typically set to open at a pressure between 8 and 15 psi, depending on the engine and the filter design. This ensures that oil can still circulate if the filter gets clogged but prevents the valve from opening too soon. It’s worth mentioning that the bypass valve doesn’t open just because you accelerate. However, if the filter is already partially blocked, high RPMs or sudden acceleration can spike oil pressure enough to trigger the valve. The valve responds to pressure, not directly to acceleration, but they’re related when it comes to oil flow.