Built in oil filter bypass on different filter

[Walravenseth]

Hello BITOG,

So I have a silverado that has a gen 3 LS in it, and I had a couple questions about selecting an oil filter for it. I was planning on going with an aftermarket oil filter, but the oil pan has a built-in oil filter bypass. So I guess here are my questions.

1. Will the different filter media and oil filter size be a problem?

It originally calls for an ACDelco pf46, but after some research here I was planning on running a microgard filter that would be the size of an ACDelco pf61. I would guess that my oil filter bypass opening pressure should change with it, but I’m not 100% sure.

2. If it is a problem, would plugging it and running an oil filter with a built in oil filter bypass be a bad idea?

My thought was if it was a problem, I could just run a microgard MSL51522 and plug the bypass. Since I’m just moving the bypass to the filter, all should be well right?

3. If it isn’t a problem, does anyone happen to know what the microgard equivalent of the pf61 without an oil filter bypass part number is?

Thanks!

Seth

 

[ZeeOSix]

It originally calls for an ACDelco pf46, but after some research here I was planning on running a microgard filter that would be the size of an ACDelco pf61.

Is it a MircoGard filter model that is specified for that engine? MicroGard Select filter seem to have a bypass valve set around 22 PSI, and I think the GM built in bypass valve is around 12 PSI. So in that case the built in bypass would open way before the oil filter bypass valve.

 

[Walravenseth]

Those pressures seem correct to me. Just a little worried about the increased pressure from a more restrictive filter leading to it being open more often that it should. They spec a MSL51042, which is the same size as a pf46. I was thinking the larger one might be nice for more filter media but am not married to the idea. I was hoping to not have a redundant bypass just in case it doesn't seal perfect so when closed it doesn't let any unfiltered oil by.

 

[ZeeOSix]

Those pressures seem correct to me. Just a little worried about the increased pressure from a more restrictive filter leading to it being open more often that it should. They spec a MSL51042, which is the same size as a pf46. I was thinking the larger one might be nice for more filter media but am not married to the idea. I was hoping to not have a redundant bypass just in case it doesn't seal perfect so when closed it doesn't let any unfiltered oil by.

I doubt the MicroGard Select is anymore flow restrictive (meaning a high dP vs flow curve) than any other filter. When you look at dP vs flow data of all kinds of oil filters, with hot oil at 10 GPM going through them, the dP across them only varies a few PSI. The MicroGard Select filters use a lot of media area. The bypass valve design used in the MicroGard Select is built into the end cap, and shouldn't leak.