Buy Genuine Cummins Turbo Actuator Kit 60 Series - wisentpartscenter.com

Description

Cummins 3787579 Turbocharger Actuator Kit - Genuine Holset 12V VGT Electronic Actuator

The Cummins 3787579 is a genuine Holset electronic actuator kit, 12 volt, for VGT turbochargers on ISM, ISX, QSM and QSX engines. It also covers Detroit Series 60 applications running the Holset VGT. The actuator takes position commands from the ECM and moves the vanes in the turbine housing, which is what sets boost.

Key Functions:

- Moves the VGT vanes to the position the ECM commands
- Sets boost across the rpm range and supports engine braking
- 12 volt electronic unit with position feedback to the ECM

Fitment & Specifications:

- Cummins ISM, ISX, QSM, QSX
- Detroit Series 60 with Holset VGT
- 12 volt

Note: Verify fitment with us before ordering to ensure the correct part for your application.

Purpose of the Part

The vanes inside a VGT turbo have to be somewhere specific for every load and rpm the engine sees, and the actuator is what puts them there. The ECM sends a target position, the actuator drives the linkage to it and reports back where it actually ended up. Close the vanes and exhaust gas squeezes through a smaller opening, so it speeds up and builds boost quicker down low. Open them and the gas slows down, which keeps boost in check up top. The same movement is what creates the restriction for engine braking.

Issue Symptoms / When to Replace

Low boost, sluggish acceleration, black smoke, weak or no engine brake, derate, and actuator position or calibration faults are the usual complaints.

Before putting a new actuator on, make sure the vanes actually move. Soot builds up in the nozzle ring on these turbos and once the vanes stick, the actuator gets commanded to a position it physically cannot reach, sets a fault and burns itself out trying. A new actuator on a seized turbo fails right away. Also check the connector and harness, since a wiring or voltage problem reads the same as a bad actuator.

Brand Information

Holset is owned by Cummins and builds the actuator, the turbo and the ECM calibration that ties them together. Vane position is what the ECM uses to control boost, so an actuator that does not hold position or report back correctly leaves the engine down on power and setting the same faults you were replacing it for.

Installation Notes

1. Key on, engine off, and open Insite.
2. Plug the new actuator into the harness but do not mount it yet.
3. Run the pre calibration in Insite.
4. Check that the vanes move freely by hand before going any further.
5. Line the turbo up and bolt the actuator on.
6. Run the final calibration.

Do not force the gear or linkage during install.

How to Identify an OEM Part

Genuine units have HOLSET cast into the housing rather than printed on or stickered, plus a label with the part number and serial number. Check that the number matches your order and that the casting looks like the original. Copies commonly leave the cast branding off, have rough casting, or put the markings on a printed label.

Why Buy 3787579 from Wisent Parts

  • ⏱️
    Fast shipping
    Orders before 12PM EST ship same business day.
  • 🛡️
    180-day warranty
    All parts covered from delivery date.
  • ↩️
    Easy returns
    30-day returns.
  • ✅
    Verify fitment
    Send VIN/ESN and we’ll confirm.

Shop with confidence

Warranty & Return Information
Warranty Information

Wisent Parts offers a 180-day warranty on all parts from the date of delivery. This warranty covers orders placed directly through our website. If a part fails during this period, we’re here to help - whether it’s a replacement, repair, or refund. For full details, refer to the Warranty page.

Return Information

Wisent Parts accepts returns within 30 days of delivery. All returns are subject to a restocking fee. To qualify, parts must be unused and in their original condition. For full return instructions and restocking fee details, please refer to the Returns page.