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O.E. Replacement DRAC Module VSSB Module Tested Refurbished


DRAC is Digital Ratio Adapter Controller (TBI DRAC, GM DRAC, Buffer Module)
VSSB is Vehicle Speed Sensor Buffer (TBI VSSB, GM VSSB, Speedometer Buffer)

Replacement Modules for failed OE applications are readily available and in stock from UD Module. DRAC and VSSB Modules fail in several ways and contribute to other systems malfunctioning on the vehicle. We offer working solutions to OE application modules due to these modules no longer being supported or available from GM. You can rely on UD Module for a remanufactured known-good tested and verified ready to plug and play solution. The external VSSB/DRAC module was used in 1989-1995 TBI Gas Chevy and GMC Vehicles and from 1990-2002 in Chevy and GMC 6.2L and 6.5L DIESEL applications.

You can order directly below. Also, helpful information is below to help with the order if needed.


Original Equipment (OE) Calibration DRAC VSSB Module
This module is calibrated based on the Broadcast Code and GM Part Number. This is a replacement for your failed factory module. We Require both the broadcast code (big 3 or 4 letters) and the part number (under the big letters), but can do on either.

PZN 16202908 can not be ordered here with this form, click this text for PZN Info and replacement.

  • Price includes tested module and core return shipping.
  • $10 Core Charge (shows as Handling) applies

  • ✔ Trusted by GM   dealers & repair shops globally.
    Broadcast Code Part Number $119
    PYT 16185145

    This module will be shipped out next day via USPS Priority Mail.
    USPS Express Mail & International Priority Mail available at checkout.




    How do I provide the information needed for an order?

    UD Module remanufactures the various DRAC/VSSB modules and then creates the exact calibrated module you need for replacement or calibration. All we need is the Broadcast code (typically 3-characters) and/or the GM Part Number (under the 3-character code) and we build you that exact module.

    First, the module will likely need to removed from the vehicle to retrieve the information. You'll need the broadcast code and the GM Part number off the old module for the order form above.

    Broadcast Code   In Blue

    Part Number   In Green



    What to do if the module is missing its label or is unreadable?

    Somewhat Unreadable

    If the module's label is unreadable on one or the other details, shoot us a picture of the module's label and contact us, you can attach an image via email. Usually we can figure it out and give you the details for your order.

    Completely Unreadable

    If the module's label is missing or completely washed out and blank, it's not a problem, we can still provide a replacement. We will need some information from your vehicle to provide a correct replacement module, this replacement will be a perfect replacement for your vehicle. Follow this link to learn more about this process and place order.

    Missing Module

    Working on a vehicle that someone has taken the module, or it is missing for some unknown reason? It's not a problem, we can still provide a replacement. We will need some information from your vehicle to provide a correct replacement module, this replacement will be a perfect replacement for your vehicle.
    Visit this link to learn more about this process and place order.


    Common Symptoms of DRAC VSSB Failure


  • ODB-I Fault code for VSS
  • ODB-II Fault code for VSS
  • Inoperative Speedometer (stays at zero)
  • Unresponsive speedometer (sits at zero then jumps to 15)
  • Jumpy Speedometer
  • Inoperative Cruise Control
  • ABS Brake System Faults
  • Transmission shifting problems 4L60E
  • Transmission shifting problems 4L80E


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