TRNW-2: 6l80 questio about sonnax pr valve

[Dan Hogan]

If you don’t drill but still the install the ball, you get no PR balance oil and high line pressure and reduced converter feed.

Sonnax re-routes balance oil directly through the stator support casting by drilling to the pr balance spool cavity.

Their PR is solid with no oil passage inside the stem like the stock design.

The stock GM PR valve and other aftermarket valves feed balance oil via the existing orifice cup plug through the PR valve stem into balance cavity. Very GM like (700-4L60E style).

If you drilled and left out the ball, I guess you may get too much balance oil as now balance oil can feed via the cup plug orifice AND the cross drilled passage. I suppose how much  depends on whether the balance spool could get pass the cup plug passage.

I suspect it would still be an unbalanced condition and pressure regulation would be borked. I think Dan Tucker posted what happens when you don’t do either awhile back as they encountered it.

—-
Dan Hogan
Buster’s Transmission Service
Matthews, NC 28105
704-847-5321
https://busterstransmissionservice.com

On Jan 3, 2025, at 7:52 PM, Wayne <wagarrick at yahoo.com> wrote:

 Dan, wouldn’t that be the case if he DID install the ball, but not drill the hole, or is this imperative with Sonnax pr valve?

Sent from my iPhone

On Jan 3, 2025, at 7:33 PM, Dan Hogan via trnw2 <trnw2 at trnw.net> wrote:

 You will have no balance oil available which means the PR valve will be located in the high pressure position in the bore.

Converter charge will be reduced significantly so you may have poor or no engagements along with overheating and high line pressure (harsh shifts).   Bad news all around.

Great article by Sonnax’s Greg Nader on how this all works. Worth the read to understand the role of balance oil and regulating.

<https://urldefense.proofpoint.com/v2/url?u=https-3A__www.sonnax.com_tech-5Fresources_131-2Danatomy-2Dof-2Da-2Dtransmission-2Doil-2Dflow-2Din-2Dthe-2Dpump-2Dpr-2Dconverter-2Dcooler-2Dlube-2Dcircuits&d=DwMFaQ&c=euGZstcaTDllvimEN8b7jXrwqOf-v5A_CdpgnVfiiMM&r=smOzNWPZu5-MBJg-0tkHhHoVW9xEBKdKWsMxBeFAJDZVJI6X79ZhQVJ_erT6I9aF&m=dvvDCt70VzBIQ4976TcvsZMYy_d-7q2fwcBu6Az1U0NZ72us__KFtXJmjY-rrUR9&s=vpd1yMgx5ZLlNhdK_tHBueD1rxFieUyvWOFgEaetD30&e=>
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Anatomy of a Transmission: Oil Flow in the Pump-PR-Converter-Cooler Lube Circuits<https://urldefense.proofpoint.com/v2/url?u=https-3A__www.sonnax.com_tech-5Fresources_131-2Danatomy-2Dof-2Da-2Dtransmission-2Doil-2Dflow-2Din-2Dthe-2Dpump-2Dpr-2Dconverter-2Dcooler-2Dlube-2Dcircuits&d=DwMFaQ&c=euGZstcaTDllvimEN8b7jXrwqOf-v5A_CdpgnVfiiMM&r=smOzNWPZu5-MBJg-0tkHhHoVW9xEBKdKWsMxBeFAJDZVJI6X79ZhQVJ_erT6I9aF&m=dvvDCt70VzBIQ4976TcvsZMYy_d-7q2fwcBu6Az1U0NZ72us__KFtXJmjY-rrUR9&s=vpd1yMgx5ZLlNhdK_tHBueD1rxFieUyvWOFgEaetD30&e=>
sonnax.com<https://urldefense.proofpoint.com/v2/url?u=https-3A__www.sonnax.com_tech-5Fresources_131-2Danatomy-2Dof-2Da-2Dtransmission-2Doil-2Dflow-2Din-2Dthe-2Dpump-2Dpr-2Dconverter-2Dcooler-2Dlube-2Dcircuits&d=DwMFaQ&c=euGZstcaTDllvimEN8b7jXrwqOf-v5A_CdpgnVfiiMM&r=smOzNWPZu5-MBJg-0tkHhHoVW9xEBKdKWsMxBeFAJDZVJI6X79ZhQVJ_erT6I9aF&m=dvvDCt70VzBIQ4976TcvsZMYy_d-7q2fwcBu6Az1U0NZ72us__KFtXJmjY-rrUR9&s=vpd1yMgx5ZLlNhdK_tHBueD1rxFieUyvWOFgEaetD30&e=>

—-
Dan Hogan
Buster’s Transmission Service
Matthews, NC 28105
704-847-5321
https://busterstransmissionservice.com

On Jan 3, 2025, at 6:47 PM, Ryan D via trnw2 <trnw2 at trnw.net> wrote:

I have a 6l80 here and the builder who built it before left out the little ball and didn't drill the hole for the sonnax pr valve. I remember reading that happened on here.
I was wondering what symptoms that would cause.
Thanks




--
Ryan
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