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Remanufactured DRAC/VSSB Modules (& Custom Calibration)
Replacement DRAC/VSSB Modules

Unique Diesel remanufactures the various DRAC/VSSB module styles and then creates the exact calibrated module you need for replacement or calibration. Every remanufactured module is verified tested and ready to be installed. 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. The external VSSB/DRAC module was used in 1989-1995 TBI Gas Chevy and GMC Vehicles in many applications. The external VSSB/DRAC module was also used in applications from 1990-2002 in Chevy and GMC 6.2L and 6.5L DIESEL applications.

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

Different terminology but the same device!

Speedometer Calibration by DRAC/VSSB

The speedometer calibration comes from physically reprogramming the DRAC or VSSB Module to replace in your vehicle. Whenever you change to a different (taller or shorter) tire or gear ratio on your truck the speedometer will be off. We can calibrate the speedometer back to the calibration that the factory sets on the these speedometers and more. Any possible gear and tire combination is supported with great granularity.

Why would you want to calibrate your speedometer?

  • Have an accuate measurement of vehicle speed.
  • Measure actual mileage onto vehicle
  • Calculate fuel mileage from odometer or trip-odometer.
  • Correct ABS (Anti-Lock Brake System) operation.
  • Correct cruise control operation.
  • Transmission shift timing and quality characteristics.
  • The DRAC/VSSB Module afffects all these and more!

  • Click on the button if you're already ready to buy.

    DRAC/VSSB Module Year/Make/Model Applications

    As mentioned above this module is primarily applicable 1989-1995 TBI Gas and 1990-2002 Diesel applications using an external VSSB or DRAC Module.

    Gas


  • 1992-1995 Chevy GMC Truck C/K 1500, 2500, 3500, 3500HD TBI gas (6,8 cylinders)
  • 1992-1995 Chevy GMC Blazer, Tahoe, Yukon TBI gas (8 cylinders)
  • 1992-1995 Chevy GMC Suburban C/K 1500, 2500 TBI gas (8 cylinders)
  • 1990-1995 Chevy Van G10, G20, G30 TBI gas (6,8 cylinders)
  • 1990-1995 GMC Van 1500, 2500, 3500 TBI gas (6,8 cylinders)
  • 1989-1995 Chevy Astro Van TBI gas (6 cylinders)
  • 1989-1995 GMC Safari Van TBI gas (6 cylinders)
  • 1989-1995 Chevy GMC S10 & Sonoma Pickups TBI gas (4,6 cylinders)
  • 1989-1995 Chevy GMC S10 Blazer, S/T15 Jimmy TBI gas (4,6 cylinders)

  • Diesel

  • 1992-2000 Chevy GMC Truck C/K 1500, 2500, 3500 6.5L Turbo Diesel
  • 1992-2002 Chevy GMC Truck C 3500HD 6.5L Turbo Diesel
  • 1994-1999 Chevy GMC Blazer, Tahoe, Yukon 6.5L Turbo Diesel
  • 1990-1999 Chevy GMC Suburban C/K 1500, 2500 6.5L Turbo Diesel
  • 1990-1995 Chevy Van G10, G20, G30 6.5 Diesel
  • 1990-1995 GMC Van 1500, 2500, 3500 6.5 Diesel
  • 1996-2002 Chevy Express G10, G20, G30 6.5L Turbo Diesel
  • 1996-2002 GMC Savana 1500, 2500, 3500 6.5L Turbo Diesel
  • 1994-1995 Hummer H1 6.5L Diesel
  • 1996-2004 Hummer H1 6.5L Turbo Diesel

  • Note: All applications for this style of module are not covered, please consult with us prior to purchase if you're unsure of your application. We will need your application, the 3 or 4 digit Broadcase code as well as GM Part number off your current module to verify this is what you need.

    Failed DRAC/VSSB Modules Symptoms in OEM Applications

    Probably a large number of visitors to this page are here to find a replacement module for their original application module that has failed. Do these modules fail? Sure! They fail in several ways and contribute to other systems malfunctioning on the vehicle. We offer working solutions to OE application modules. These modules are simply not supported or available from GM over the counter for most applications. Finding the correct direct replacement module is very difficult in the used market, say at the salvage yard or online. Ebay offers random modules for sale that don't match your exact need. No problem, we provide an OE refurbished replacement.

    Common Symptons 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


  • How to Buy


    OE Calibration Module

    Custom Calibration Module

    DIY Module
    Broadcast
    Code

    In Blue


    Example Stock Module
    Part
    Number

    In Green

    Modules ship with USPS Priority Mail (Express Available).
    Modules ship internationally with USPS Priority Mail.
    Module combinations ship next day Monday - Saturday.

    Original Equipment (OE) Calibration DRAC VSSB Module
    This module is calibrated based on the Broadcast Code and GM Part Number. This is intended to be a replacement module to replace your failed factory module. We Require both the broadcast code and the part number, 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
  • Broadcast Code Part Number $119
    PYT 16185145

    Custom Calibration DRAC VSSB Based on Gear Ratio & Tire Size
    This module is calibrated based on gear ratio and tire size. This calibration will get you a factory quality calibration with GM type gear ratios as well as aftermarket gear ratio combinations. Got a Ford rear differential gear in your GM with a different ratio than commonly available? No Problem! We can calibrate for any gear ratio or tire size.

    Please fill the form to the right out to the best of your abilities. We need to know your gear ratio and tire size and the type of DRAC module your vehicle or configuration needs. DRAC type can be determined best by it's part number and broadcast code. We can also determine the type by the application (Year, Model, Series, Engine).

    If in doubt about what you need to enter, contact us and we'll walk you though it. Taking a picture of the inside of the module will help as well.



  • Price includes tested module and core return shipping.
  • $10 Core Charge (shows as Handling) applies
  • DRAC Type Setting Quality $119
    Year, Model, Series, Engine
    1995 Suburban K2500 6.5 Diesel
    Tire Size Gear Ratio
    245 75 R16 4.10
    Broadcast Code, GM Part Number
    PYT, 16185145

    OE or Custom Calibration DRAC VSSB Module with "Tech Support"
    This module is calibrated based on OE Broadcast and GM Part Number or gear ratio and tire size

    Please fill the form to the right out to the best of your abilities (fields are all optional). We need to know your gear ratio and tire size and the type of DRAC module your vehicle or configuration needs. DRAC type can be determined best by it's part number and broadcast code. We can also determine the type by the application (Year, Model, Series, Engine).

    This module includes Tech Support in the form email guidance through explanation of how the system works, wiring diagrams, test procecures for the module and various systems it operates. This tech support is tailored to your vehicle's application.

    Includes up to 20 email responses and is based on a per incident per purchase limitation. Must own an Digital Multimeter for test procedures. valid throughout the duration of warranty on the new module.

  • Price includes tested module, and tech support.
  • $10 Core Charge (shows as Handling) applies
  • DRAC Type Setting Quality $169
    Year, Model, Series, Engine
    1995 Suburban K2500 6.5 Diesel
    Tire Size Gear Ratio
    245 75 R16 4.10
    Broadcast Code, GM Part Number
    PYT, 16185145

    DRAC VSSB "Tech Support" for Unique Diesel Modules ONLY
    This is for Technical Service in the form of email guidance through explanation of how the system works, wiring diagrams, pinouts, test procedures for the module and various systems it operates. This tech support is tailored to your vehicle's application. Must already own a Unique Diesel remanufactured Module, enter code found on bottom right hand cornder of DRAC label in the form "UD Code"

    Includes up to 20 email responses and is based on a per incident per perchase limitation that is effective for 30-Days after purchase. Must own a Digital Multimeter for test procedures.

  • Price includes email tech support only, no parts.
  • Year, Model, Series, Engine $85
    1995 Suburban K2500 6.5 Diesel
    UD Code

    H1 Hummer VSSB OE Module & Custom Calibration
    UD can provide original equipment calibrations for H1 Hummers for stock tire size and stock gear sets. If you've swapped your gears but not tires we can get you the OE calibration that matches that new gear. Got a custom gear set and different tire size? We can do that too, click on the more info to the right to learn more.

  • Price includes refurbished module, and mounting velcro
  • $10 Core Charge (shows as Handling) applies
  • $125


    Do It Yourself (DIY) Dip Switch DRAC VSSB Module
    This user-calibratable module equipped with DIP Switches is for when you want to keep your OE module and calibrate it for your own application. This module can be user-calibrated via the dip switches based on your own math and calculations for your gear ratio and tire size. This module carries no support.

  • $10 Core Charge (shows as Handling) applies
  • DRAC Type $119
    Select From List


    Shipping Options

    USA Priority Mail
    USPS Priority Mail with Delivery in 2-4 Business days after pickup in the USA 50 States. Default shipping method.
    $7.20
    USA Express
    USPS Express Mail with Delivery in 1-2 Business days after pickup in the USA 50 States. Availble during checkout.
    $23.00
    Canada Priority
    USPS Priority Mail with Delivery in 1-2 weeks via Canada Post. Available during checkout for Canadian Addresses.
    $15.00
    GlobalPriority
    USPS Global International Mail with Delivery in 1-2 weeks via local Post. Available during checkout for all Countries.
    $25.00


    Shipping Procedures

    All module combinations are in stock and ready to ship as soon as ordered. This is for OE, Custom calibrated and DIY modules. Modules will be delayed in shipping if we do not receive all the information on the module requested or if the information provided does not match our data.

    Shipping for USA Domestic Priority and Express orders will ship the next day after an order, except Saturday (can't deliver to USPS on Sunday). Canada and International orders ship next day after order Monday - Friday only. Tracking information is uploaded to Paypal 100% of the time so you'll know your package is on the way.

    Canada and International orders: The shipping prices are discounted by the core charge of the module that appears as handling. This is because it is typically not economical for the customer to return a core module outside of the USA.

    $10 Core Charge "Handling" Charge

    The "handling" charge on your purchase is the Module Core Charge. Included with your new module is a pre-paid labeled envelope that you can use to ship your core module back to Unique Diesel. Just enclose your module in the envelope and place in your mailbox and USPS will pick this up, you can also drop off at any USPS Receiving Box. Once the core module has been returned you will receive a $10 refund, this will apply to your Paypal or Card. Core returns must be received within 30 Days of purchase to be eligble for the $10 refund. Cores will still be accepted after 30 days and are still appreciated.

    Warranty

    All DRAC/VSSB Modules carry a 90 Day Warranty on the original part. If for any reason the module fails to perform as designed you may send the module back for exchange. Suspected defective modules must be returned to Unique Diesel for testing and evaluation. Warranty coverage is the form of exchange only and replacement is at the discretion of Unique Diesel. Multiple exchanges for modules cannot occur only one exchange part will be serviced. Corrective calibrations can occur under warranty only during the 90 day period. Dismantling, alteration and modification voids all warranty on the unit.

    Technical Support:

    By purchasing a standard remanufactured module Unique Diesel does not offer any technical services for troubleshooting your application with that DRAC VSSB module. Technical services may be purchased separately.

    Modules with Tech Support offer guidance and documentation resources provided via email only. Tech Support services does not guarantee correction of vehicle problems as this is the responsibility of the shop or owner of the vehicle to correct. The tech support is simply guidance towards finding the real problem performed remotely via email. Tech support service only available for UD Remanufactured modules.

    Module Testing:

    Unique Diesel does not test modules pre-purchase. The best way to verify you have either a defective module or a vehicle fault is to test with a known-good module.

    DIY Module Warranty:

    DIY Modules carry a 90 day parts warranty and offer no support. Correct application of the right type of module for the application is the buyers responsibility. Exchange units may be available for the wrong module purchased at the buyer's expense for shipping back and forth.

    Frequently Asked Questions

    What if I don't have my numbers off the module?

    You can shoot an image and email it to Unique Diesel of the inside of the case of the board and we can identify it for you as well as the ratio that the replacement needs to be set at.

    What if I don't know what module I have?

    Email a pic of the board to Unique Diesel and we'll indentify it for you.

    How can I ship the module back cheaply!

    We prefer the US Postal Service Small Flat Rate Box. Shipping rates are around $7

    Copyright 2018 Unique Diesel