2017-2024 6.6L Duramax L5P Installation


1. Included with Purchase
2. Step by Step Instructions
3. How The Selector Switch Works
4. Check Engine Light Troubleshooting
5. Remove Module Before Service

Included With Purchase

(1x) Dr. Performance Module
(1x) Wire harness with fuel rail sensor connections
(2x) Zip ties
(1x) Install instructions
(1x) Selector switch if purchased

Step by Step Instructions

Be sure your truck has been off, with the hood unlatched and key fob located away from the vehicle for at least 15 minutes before installing the module. Key fob needs to continue to stay away from the vehicle for the entire installation process. This allows the computer to 'sleep' and for your engine compartment to cool down. It also helps mitigate your ECM from detecting an interruption in a sensors electrical circuit.

Step 1

Locate the sensor connections shown below.

Step 2

Disconnect the factory plug - the red locking latch must be pulled back on the plug before it can be released.

Step 3

Connect the module's harness plug into the factory harness receptacle. Push the red locking latch forward to secure the connection.

Step 4

Connect the factory harness plug into the module’s harness. Push the red locking latch forward to secure the connection.

Step 5

Route the module’s harness towards the passenger side fender well.

Step 6

Connect the module into the harness.

Step 7

Connect the selector switch into the module’s harness. (Run into the cab or leave tied up with the module under the hood).

Step 8

Secure the module as desired (with zip ties provided or velcro, etc.) away from heat/moving parts.

How The Selector Switch Works

The dial going clockwise:

Stock - Low - Medium - High

Low: Towing heavy and low traction situations.

Medium: Moderate towing and ideal for everyday driving situations.

High: Maximum performance - ideal for empty highway cruising.

The switch must remain plugged in to stay in the desired setting. You can run the switch into the cab or leave it tied up under the hood. Leave in one setting as much as possible.

Everyone has different driving preferences, it’s suggested that you try each setting for at least a week to see what you prefer.

If You Get a Check Engine Light or Hard Start Upon Installation

Please check the connection between the truck’s wire harness and the module’s female plug and ensure it was connected properly. Improper installation will cause a CEL/hard starting.

Remove The Module Before Service Work

If you need to take your vehicle in for service work, REMOVE the module before work is performed.

If you have any issues, please call (800) 406-5257 and one of our techs will be happy to help!