[Blown353]

The new M55HV pumps are the thinner wall thickness castings too (you shouldn't be needing an HV pump for 99% of applications anyways but that's another story entirely...)

The only way to make sure you're getting the good THICK wall thickness pumps is to buy any of the pumps in their "Select" line.

All spur-gear type oil pumps will experience some amount of cavitation at some point in their operating range. This cavitation, coupled with general vibration in the engine will induce a cyclic load on the pump body. If the pump body isn't thick enough it will eventually crack and fail.

I have seen several of the new "thin" pumps fail now in roundy-round applications but I also know several other roundy-round guys who have an entire season on the thin pumps with no cracks of any kind even after a penetrant inspection. They are switching to the "select" pumps for next season though.

It's only a few bucks more for the original thicker casting pumps-- why take the chance?

Melling's wrongdoing in this case was not getting the word out to the "performance" crowd in a better manner.

Word has it that sometime in the near future Melling is going to be releasing a gerotor-type pump for Chevy's under their "select" line... that will be cool.