Heater Core
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CARQUEST Heater Core

Part No. 399903 Warranty Details  

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Please note: Advance Auto Parts is proud to carry comparable exact-fit parts from multiple vendors, as such, the item you receive may be one of two quality brands. Both brands meet the same fitment requirements and are equal in their performance and specifications.

Our heaters are designed and tested to meet or exceed OE specifications for form, fit, and function. Using premium quality materials and a clear focus on the highest heat transfer performance possible, our engineers have designed this heater to perform at the highest standards to ensure a warm cab environment during those cold winter months.
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Construction:Expanded Tube
Core Height:9 1/4 in
Core Material:Plastic Tank / Aluminum
Depth:1 5/8 in
Inlet Connection Type:5/8 in
Inlet Diameter:3/4 in
Outlet Connection Type:5/8 in
Outlet Diameter:3/4 in
Tank Material:Plastic
Thickness:1 5/8 in
Width:6 1/4 in

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3 Questions | 3 Answers
Displaying questions 1-3
  • Q:

    Does this use , coolaint to give heat from the motor to the cabin of the car.
    Asked on 8/16/2013 by lundy

    1 answer



      The heating core uses hot engine coolant to warm the inside of your vehicle. When you turn the heater on, a blower motor begins to spin a fan or blower. An inlet hose brings hot coolant into the core, which is essentially a small radiator under the dashboard. As the hot coolant travels through a series of tubes inside the core, fins surrounding the unit begin to dissipate the heat into the outside air. The fan then blows this heat through ducts and into the cabin. For any further assistance, please feel free to call us at: 1-877-238-2623 or visit the nearest Advance Auto Parts store and one of our Parts Pros will gladly assist you with any questions or concerns you may have.

      Answered on 8/18/2013 by Steve from AAP
  • Q:

    can you run your car without a heater core?
    Asked on 11/14/2010 by leon from palmdale, ca.

    1 answer



      It is possible, but you would need to take the heater hoses off and plug the lines or route them into each other.

      Answered on 11/16/2010 by Mike the Auto Parts Master from AAP
  • Q:

    How difficult is it to install?
    Asked on 10/16/2009 by Anonymous from Lititz, Pa.

    1 answer



      Some vehicles it is very difficult. Some you have to take out the whole dash. i Highly reccomend that you go to your nearest store and buy a chilton or haynes repair manual for your vehicle.

      Answered on 10/16/2009 by kevin from Advance Auto Parts
Displaying questions 1-3

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