Shadow351
SHO Member
Just a heads up that Melling now has a high volume oil pump for the 3.5L Engines.
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This. With tight bearing clearances you shouldn't need any extra flow. But with looser bearings, whether from wear or purposely for a thicker oil film, you need more flow to maintain pressure.There are pros and cons to a high volume pump.
If the engine is tight (newly rebuilt?), it just dumps the extra volume out the bypass valve. But once the engine loose is loose (high mileage) it can help keep the engine from starving for oil at low RPMs.
Conversely, it can flood the heads if too much oil gets up there.
It would be interesting to see a before-and-after with a catch can and see if more oil winds up in the PCV![]()