LB7 Standalone Harness

DmaxSwap.com has worked to develop the cleanest solution for wiring your Duramax drivetrain for simple operation with nothing more than power, ground, ignition and cranking signals. This harness is the connection between the ECM/TCM and the engine harness as well as the transmission. This Product is a pre-built Standalone Harness built from a good used OEM harness and designed to run your 2001-2004 LB7 engine and Allison 5 speed transmission (it may also be configured for engine only for use with manual transmission or other standalone transmissions)

* This harness is currently out of stock please Contact us for availability.

** This harness requires ECM tuning and we recommend TCM tuning as well (see the explanation in our article, Duramax Swap Custom Tuning).

*** If you have a good donor harness and would like to send it in for inspection we can make an offer to purchase your donor $150-$400 depending on condition Contact us.

If this Harness is available on the website then it should be in stock and ready to ship within 1-2 business days (excluding holidays). “Engine Only” will add 2-3 week lead time as we typically don’t stock these. More information below.

Out of stock

This product is currently out of stock and unavailable.

SKU: sah-lbz Categories: ,
 

Description

Duramax engine and transmission harness for standalone use as follows:

  • Entire Harness inspected, cleaned and re-loomed
  • Retain Allison TCM or setup for “Engine Only”
  • Reconfigure harness for individual connector runs and a centralized ground.
  • Install a single fuse block and provide a main ignition power relay.
  • Install 12v Constant Fuse Link.
  • Install OBD2/ALDL Connector – 4 Feet Long. All OEM diagnostics procedures and DTC’s will function the vehicle the powertrain was removed from.
  • Retain Duramax Alternator controlled by PCM.
  • Cruise Control pigtail connections and provide schematic.
  • Air Conditioning control related circuits are not part of the standalone harness (to be controlled by your HVAC system)
  • Remove Coolant Level indicator control circuit.
  • Wait to Start (WTS), Torque Converter Clutch (TCC), 4wd low and MIL lamp pigtail connections to PCM
  • Tach and Speedometer pigtail connections
  • Every harness is completely opened and electrically tested. No shortcuts!
  • Simple 4 wire hook up to make the engine run. (A Single Ground, 12V Constant, 12V Key On)


* Can be recovered with new High Temp Loom and High Temp Harness Tape.

The harness can be configured to include following Inputs and outputs:

Inputs:

  • Cruise Control
  • 2wd/4wd operation

Outputs:

  • Speedo signal
  • Tachometer
  • Fuel pump relay
  • AC clutch command

Important info about our harnesses…

Lead time on harness conversion is generally 3-4 weeks from the time it is received and checked in. At the time of check-in, the harness will be inspected and subject to additional charges (either mandatory or suggested) if there are any issues with wires, corrosion, pins or connectors.

We do not support Duramax integration into late model vehicles. This includes any integration with any factory gauges, factory body harnesses, etc. It doesn’t mean it can’t be done, just that we don’t support it. You will not retain control of the AC, tow haul or any other factory features that are controlled through the BCM.

Your harness is set up for standalone use only which in basic terms means the engine will run and the transmission will function. Due to the complexity of modern vehicles and their control systems, donor vehicle functions, conveniences or “nice to haves” are not offered or supported in any way as follows:

Tow-Haul Mode, Tap Shift, Electric Transfer Case Shifting, Axle Engagement, Duramax Idle Up, Fled Fuel, Starter Solenoid Control, Park-Neutral Starter Interrupt, Shift Interlock, AC Compressor Clutch Control, AC Req Idle-Up, AC Req Fan Control, Cruise Control, Vehicle Lighting, Donor Vehicle Gauge Clusters or any other donor vehicle features/conveniences.

You will be responsible for wiring your owner starter circuit with neutral safety and your own AC circuit if you are wanting AC. You can still leverage any of the factory AC components you’d like but it will be controlled separate from the harness. We recommend aftermarket HVAC, controls and dryer at least.

Gauges: We offer a 10% discount on any available Dakota Digital products with the purchase of our harness (contact us with specific product requests). The harness will retain the OBD port, so you can use that for your gauges or use some of the harness pigtails and add an oil pressure and coolant temp sensor to wire them directly. We recommend the latter if you’re planning to use the OBD continually for anything else because the signal isn’t always strong enough on an OBD splitter to run two devices. The CTS3 monitor can be used as a gauge cluster as well.

If you are interested in our standalone harness you can follow our ordering guide, purchase your harness modification a well as the ECM and TCM tunes and we can certainly get it running and driving properly for you.

Disclaimer

Any attempts to make the above mentioned systems or features function are completely up to the customer and/or the installer.

Modifications will void any warranty or support, so it is crucial that you test start your setup with the harness prior to making any modifications. If you have not made modifications to the standalone harness, have proper tuning and are having issues with your test start, please see our diagnostics form.

Additional information

Weight 10 lbs
Dimensions 24 × 12 × 6 in
LB7 Model

2001-2002 LB7, 2003-2004 LB7

Transmission Type

Engine Only (Manual/Other standalone transmission), Allison 5 Speed (LB7/LLY)