Current turnaround: 2 weeks

Shop hours 8 AM ET, Monday–Friday

Email responses are usually within 6 hours every day

Start Send In
Duramax standalone harness conversions
  • LB7
  • LLY
  • LBZ
  • LMM

Leave it to us.

The typical Duramax harness has hundreds of individual wires and each has a specific place in the harness. Rely on our knowledge and experience instead.

Start Send InShop new harnesses
From your truck to our bench and back.How it works
  1. 01Start online

    Tell us about your harness

  2. 02Ship it in

    To our shop in Melbourne, FL

  3. 03Converted & refreshed

    Peeled, cleaned and inspected

  4. 04Back to you

    2 weeks turnaround

Send in service

Send us your harness.It comes back refreshed.

Your Duramax ECM/TCM harness from a pickup truck, converted to standalone, cleaned, inspected and recovered.

Finished Duramax standalone harness with labeled wires and connectors
  • LB7
  • LLY
  • LBZ
  • LMM
$576

Duramax ECM/TCM standalone conversion

Your LB7, LLY, LBZ, or LMM harness, reworked for standalone use. Completely cleaned, inspected, and refreshed.

  • Delphi fuse and relay block
  • 5-foot OBD port
  • Donor truck pedal connector
Start Send InWhat to send
Upper engine harness before its complete refreshBEFORE THE REFRESH
SEND ONE HARNESS. OR BOTH.+$500

Upper engine harness refresh

Your upper engine harness gets the same attention: peeled, degreased, inspected, and recovered with high-temperature tubing and tape.

Added to a standalone conversion.

Add your harness details
No harness to send?All new one piece LBZ and LMM harnesses.Built new and set up with the options you choose. See the shop.
How we can help

Pick your starting point.Harnesses are our only business.

Our process

Much more thanadding a fuse block.

Here’s what we do to every harness that comes through our door.

  1. Step 1

    Tagged

    Your donor harness is tagged with your work order when it arrives.

  2. Step 2

    Peeled

    All the old loom tubing and tape comes off, exposing the harness underneath.

  3. Step 3

    Degreased

    The harness is completely cleaned and degreased before inspection.

  4. Step 4

    Inspected

    Every terminal and bulk wire run is checked under magnification.

  5. Step 5

    Work order call

    Expect a work order phone call 3–4 business days after your harness arrives.

  6. Step 6

    Finished & shipped

    Recovered with high-temperature loom, tape, and printed labels, then packed for its return.

High-temperature split loom. GM-spec tape. Printed plastic labels. Every detail matters.

More about the process
Ready when you are

Ready to send yours in?We’ll take it from there.

See what to remove, add your contact details, and get the shipping address.

Start Send InHave a question? Contact us