Safely enable Trim on Yosemite and El Capitan!

Safely enable Trim on Yosemite and El Capitan!
July 2, 2015 Oskar

I am very happy to announce the new method to enable Trim on OS X Yosemite and El Capitan.

Using Disk Sensei or Trim Enabler, you can now enable Trim on OS X Yosemite (10.10.3 or later) and OS X El Capitan without disabling kext signing!

Thanks to new functionality introduced by Apple, I’ve been able to develop a driver that can enable Trim without modifying your system in any way. This is a huge breakthrough for Trim on OS X!

This means that:

Disabling kext signing is no longer necessary!
The “gray boot screen/stop sign” issue is gone!
Your system is no longer modified in any way!
Trim will no longer reset on updates!

This is the easiest and safest way to enable Trim on OS X. It is even better than using the new built in trimforce command, since that requires 10.10.4 and may require disabling system security on El Cap.

Here’s how to enable Trim safely on OS X Yosemite or El Capitan:

Disable Trim with your current Trim-tool of your choice (if you already have it enabled)
Download Disk Sensei (if you have it, update to version 1.2)
Open Disk Sensei and select Tools -> Trim
Enable Trim and reboot

Safe Trim Enabling is part of Disk Sensei update 1.2 and Trim Enabler 3.1. Full change logs:

Disk Sensei 1.2:
– Revamped Trim Enabling: Disk Sensei now uses a custom Cindori driver to safely enable Trim for 3rd party drives!
– Added OS X El Capitan support
– Added OS X 10.10.4 support
– Fixed an issue where Health (S.M.A.R.T) updates would trigger heavy drive load
– Fixed an issue with the center label in the Visual feature
– Fixed an issue with the Trim switch
– Added 7-day trial mode

Trim Enabler 3.4:
– Revamped Trim Enabling: Trim Enabler now uses a custom Cindori driver to safely enable Trim for 3rd party drives!
– Added OS X El Capitan support
– Added OS X 10.10.4 support

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  1. wclyffe 4 years ago

    Oskar, don’t you mean Trim Enabler 3.4 coming later today?

  2. homever 4 years ago

    ….. may require disabling system security on El Cap.

    Should a “temporarily” be added?

  3. Jose Salas 4 years ago

    I’ve followed your instructions and now the stop icon appears even booting with the hd drive. I can’t access to the system. At least before this, this happened only if I tryed to boot from the ssd drive.
    Don’t know what to do now.

    • Oskar Groth 4 years ago

      Did you re-enable kext-signing? That could make other stuff break and cause the stop sign, if you have unsigned kexts installed. Disk Sensei 1.2 can not cause the stop sign by itself.

    • Mike Johnson 4 years ago

      I’ve had the same experience as Jose. I disabled Trim with Trim Enabler a few days ago and re-eanbled kext signing. I also purchased Disk Sensei and installed it (leaving Trim Enabler installed but disabled). Tonight, I upgraded Disk Sensei, enabled Trim in Disk Sensei and was greeted with the dreaded gray screen on boot. I followed your instructions at to get back to having a bootable system. My hunch is that I should have uninstalled Trim Enabler, but I’m not sure. I have another system at work to update. I’ll see what happens with it.

  4. Valentino 4 years ago

    Disabling Trim with my current Trim-tool (Trim Enabler 3.3) automatically re-enable kext signing on my Mac? Thank you.

  5. kusuma 4 years ago

    Does this mean by using Disk Sensei 1.2 is safe to update to Yosemite 10.10.4 and El Capitan public beta (when it comes out) without worrying kext problem?

    • Cpuroast 4 years ago

      That’s the idea, yes 🙂
      It no longer requires disabling kext signing and therefore leaves your system in a pristine, secure state, minus the extra signed kext it installs to enable trim.

  6. yuri 4 years ago

    Has the updated Trim Enabler already come out? You are doing a good job Oskar, but your time estimates are a bit off 😉

    • Oskar Groth 4 years ago

      Indeed, sorry about this. Working on it. Although I do encourage everyone to just download Disk Sensei instead, there is no reason to use Trim Enabler over Disk Sensei. Disk Sensei is much better option to enable Trim for everyone on OS X 10.9 or above.

  7. Ali Servet Donmez 4 years ago

    Hi, I have purchased back then Trim Enabled only, but I never used Disk Sensei. Does that mean Trim Enabler is not necessary any more for someone like me who didn’t use Disk Sensei anyway?

  8. Dzmitry 4 years ago

    Hi Oscar, thank you for your work you’re doing for the old MacBooks society. I joined the network of those who had issues with TRIM and purchased TRIM Enabler 2 or 3 weeks ago, right before the Apple fixed the issue. Since, you’re encouraging everyone to switch to Disk Sensei I’m wondering if you have in mind to offer discounted options for those who has already purchased TRIM Enabler and is considering to switch to Disk Sensei, so that not to pay for the TRIM function twice?

    Thank you.

  9. Billy 4 years ago

    So another $10 just to get the update?

    • Oskar Groth 4 years ago

      No, $10 to upgrade from Trim Enabler to Disk Sensei, which is a completely new software that is replacing Trim Enabler.

  10. Billy 4 years ago

    So I take it that you have stopes supporting trim enabler just because you want more money?

    Dude, that is ghetto.

  11. Chris 4 years ago

    Thanks for the update. So I updated to the new Trim Enabler without disabling it with the older version. Would kext signing have been reenabled just by updating to the new version or do I have to do something? How can I check?

    • Chris 4 years ago

      Oh, and right now whenever I check Trim Enabler it says “Trim has not been enabled through Trim Enabler, but is working anyway.” Trying to enable it and reboot doesn’t change this.

      • Chris 4 years ago

        So I uninstalled Trim Enabler 3.4 through the app and restarted. When I check my system report, however, it has a “Yes” value for Trim Support for my Samsung SSD. I’m confused.

        • Oskar Groth 4 years ago

          Make sure you first disable using an old version of Trim Enabler.
          It will restore kext-signing for you as well.
          You can download the 3.3 version here:
          Once you have disabled and rebooted, use the 3.4 version.

          • Larry 4 years ago

            Hi Oskar, I made the same mistake as Chris and installed Trim Enabler 3.4 without disabling Trim with version 3.3. I see you provided a link to the older version to disable Trim and restore the modified kext file. But when I install the file from the link you provided, I still end up with Trim Enabler 3.4. Please help me get my modified kext file back to how it was. Thank you, Larry

  12. Jarrod 4 years ago

    Hi Oskar,

    I currently have Trim Enabler 3.4 installed onto my machine. I will upgrade to Disk Sensei – but I was wondering how best to go about the change over? Just download DS onto my machine & install / enable, then completely delete TE from my machine?

    Do I receive a discount? I have been using TE for a long time & it works / has worked fine for me.

    I can’t wait to upgrade to EL Cap when that comes out & am glad I won’t have to worry about the grey screen anymore with updating.