Several years back (on the old forum), I learned of a fixed orifice PCV valve used on the LS engines that would also fit the L31. This info was provided in a post by NJCKZ71:
"Replace the L31 PCV valve with the fixed orifice unit and thank me later - P/N 12572717"
I wish he was still around here, as he was one of our resident engineers and an extremely smart guy. I learned a lot from his posts, which is why I copied and pasted many of them into Wordpad documents for later reference (this PCV valve, case in point).
So, I looked into it since the PCV valve in my mom's 99 Tahoe was buzzing. Thought this would be a good time to try this out. As to GM's reason for doing this, here is some background on the fixed orifice valve:
Procured one of these along with a stock L31 valve (both in AC-Delco as those are the ONLY PCV valves I use) from the local Delco distributor and took a few pics before the install:
So far so good. Everything seems fine, but I will be keeping an eye on oil level to track any possible consumption change or other effects. I was wondering if anyone else here has tried this, and if so, what is the verdict?