[ctrlz]

Originally Posted by AspiringCarGuy

I wonder if using the heavier 40 weight oil had anything to do with it, even though it's recommended by the manual for track duty.

That's my personal working theory. heavier weight oil leads to slower drainback causing pump cavitation and destruction. That pump stator always fractures at the weakest point, which is where it is cut out for a pivot. I have posted more on this in other threads. This pump was originally designed for the Chevy cruze, and made it over to many other models as a fuel economy enhancer. needless to say, the cruze wasn't intended for 40 weight oils.

To those who might say, "Well, chevy now recommends 40 weight oils for these cars," my response would be, "This is the same company that keeps using this pump that fails."

[Vigilante375]

Originally Posted by ctrlz

That's my personal working theory. heavier weight oil leads to slower drainback causing pump cavitation and destruction. That pump stator always fractures at the weakest point, which is where it is cut out for a pivot. I have posted more on this in other threads. This pump was originally designed for the Chevy cruze, and made it over to many other models as a fuel economy enhancer. needless to say, the cruze wasn't intended for 40 weight oils.

To those who might say, "Well, chevy now recommends 40 weight oils for these cars," my response would be, "This is the same company that keeps using this pump that fails."

When the oil pumps started failing, were for the year models that GM recommended 5w30, not 0w40. 0w40 came out as the official oil for street and track use (for non 1LE ZL1's) in late 2018 for the 2019 year model.

I didn't know the oil pump was from a Cruze. Is this true for the LT4 in the CTS-V and Z06? If it is, then why are did the ZL1 oil pumps fail but not the CTS-V or Z06 oil pumps when they use the same oil?

[gblaue]

Originally Posted by Vigilante375

When the oil pumps started failing, were for the year models that GM recommended 5w30, not 0w40. 0w40 came out as the official oil for street and track use (for non 1LE ZL1's) in late 2018 for the 2019 year model.

I didn't know the oil pump was from a Cruze. Is this true for the LT4 in the CTS-V and Z06? If it is, then why are did the ZL1 oil pumps fail but not the CTS-V or Z06 oil pumps when they use the same oil?

I agree. I change my oil to 0W4 when GM made the change in 2019. They just didn't decide to make that change out of the blue. At 38k miles, I still had no pump failure. I did have my pump changed out to a Katech anyways.

I am not si sure about the CTS-V, but the Z06 was a dry sump, so it would have never of had this issue.

[Camfab]

Likely so few units in total with respect to the LT4 that GM knows it’s cheaper to repair a few cars while in warranty rather redesign the part. Once you’re out of warranty it’s your problem.
I don’t see the LT4 in any other future car.

[ctrlz]

Originally Posted by Camfab

Likely so few units in total with respect to the LT4 that GM knows it’s cheaper to repair a few cars while in warranty rather redesign the part.

Agree 100%.