Vacuum Bypass Closes Heater Valve
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CARQUEST Vacuum Bypass Closes Heater Valve

Part No. 74781 Warranty Details  

See if this part fits a specific vehicle.

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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 products are engineered and tested to provide years of trouble free operation. Backed by over 50 years of mobile a/c experience, fix it once and fix it right with Factory Air.

Product Features:
  • Temperature tested to 270 degrees F
  • Pressure tested to ensure leak free design
  • Vacuum controlled
  • Application specific design
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Fitting Size:5/8 x 3/4 x 5/8 x 3/4 in
Hose #1 Size:.625 in
Hose #2 Size:.75 in
Material:Plastic
Operation Type:Vacuum Closes, Bypass
Type:Vacuum Closes, Bypass

REVIEW SNAPSHOT®

by PowerReviews
CARQUEST or Factory AirVacuum Bypass Closes Heater Valve
 
3.6

(based on 5 reviews)

Ratings Distribution

  • 5 Stars

     

    (1)

  • 4 Stars

     

    (2)

  • 3 Stars

     

    (1)

  • 2 Stars

     

    (1)

  • 1 Stars

     

    (0)

80%

of respondents would recommend this to a friend.

Pros

  • Easy to install (3)

Cons

No Cons

Best Uses

  • Everyday driving (4)
  • Replacement (4)
    • Reviewer Profile:
    • Casual driver (3)

Reviewed by 5 customers

Displaying reviews 1-5

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5.0

had in stock

By 

from aurora,co

Verified Buyer

Pros

  • Exactly Like The Original
  • On The Shelf
  • Perfect Fit

Cons

    Best Uses

      Comments about CARQUEST or Factory Air Vacuum Bypass Closes Heater Valve:

      no special order, had on shelf, and it matches 100 percent. just like the factory part.

      • Was this a gift?:
      • No

      Comment on this reviewHelp Icon

       
      3.0

      Lowest Price on a suburban heater valve

      By 

      from Gainesville GA

      About Me Auto Enthusiast, Casual Driver, Competitive Driver, Mechanic

      Verified Buyer

      Pros

      • Lightweight

      Cons

      • Cheap
      • Difficult To Install
      • No Improvement In Performance

      Best Uses

      • Everyday Driving
      • Replacement
      • Replace That Leaking One

      Comments about CARQUEST or Factory Air Vacuum Bypass Closes Heater Valve:

      This part is lightweight and plastic, but is tucked in next to the right front fender liner and well protected from accidental damage. If you replace this, replace all the water hoses and the vacuum hose that connect to it too. Don't clamp down on this with a worm clamp, retain the OEM hose clamps if you can get to them. If you are in there already, it may be time to replace your A/C manifold hoses, they start to break down after 15 years.

      Comment on this reviewHelp Icon

      (0 of 2 customers found this review helpful)

       
      4.0

      great bang for the buck

      By 

      from Russell,ks

      About Me Casual Driver

      Verified Buyer

      Pros

      • Easy To Install

      Cons

        Best Uses

        • Everyday Driving
        • Replacement

        Comments about CARQUEST or Factory Air Vacuum Bypass Closes Heater Valve:

        Bought product to replace old cracked one. very easy and quick tp replace.

        Comment on this reviewHelp Icon

        (3 of 3 customers found this review helpful)

         
        2.0

        Didn't last long..

        By 

        from Claxton, GA

        About Me Auto Enthusiast, Mechanic, Truck Enthusiast

        See all my reviews

        Helpful Reviewer

        Pros

        • Easy To Install
        • Inexpensive

        Cons

        • Cheaply made

        Best Uses

        • Everyday Driving
        • Replacement

        Comments about CARQUEST or Factory Air Vacuum Bypass Closes Heater Valve:

        Installed on my 1995 Yukon and it came apart where it's glued/welded together and spewed coolant after only a few months.

        Comment on this reviewHelp Icon

        (7 of 7 customers found this review helpful)

         
        4.0

        No more vanishing anti-freeze

        By 

        from Huber Heights, OH

        About Me Casual Driver

        See all my reviews

        Ask me a question

        Verified Buyer
        3 or more reviews submitted

        Pros

        • Easy To Install
        • Value priced

        Cons

          Best Uses

          • Everyday Driving
          • Replacement

          Comments about CARQUEST or Factory Air Vacuum Bypass Closes Heater Valve:

          Was losing anti-freeze and couldn't see any leaks around major hoses (radiator and heater) then I noticed wetness on the frame directly below this valve. The frame was preventing the antifreeze from making it to the ground, so I never saw a wet spot under my Tahoe. My valve was leaking through the diaphram and possibly from one of the lower hose connections. Removed and replaced the valve with this after market exact replacement. If it holds up this will be a great fix! The price was 1/3 of the dealer's replacement part! My vacuum hose was deteriorated too so you want to check that connection too. That was a 99 cent fix, also available from Advance Auto Parts. I always look for promotion codes on-line which even makes it a sweeter deal. Thanks!

          Comment on this reviewHelp Icon

          Displaying reviews 1-5

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          Do you have questions about this product?

           

          Ask a question, get answers from real customers and in-house experts. For further assistance, please review your support options on our Contact Us page.

          5 Questions | 6 Answers
          Displaying questions 1-5
          • Q:

            I have a 1996 suburban 1500 5.7 with rear heat and air. I don't see a valve for that replacement.is there one?
            Asked on 9/7/2013 by greg from toledo,oh

            1 answer

            • CUSTOMER CARE

              A:

              Unfortunately, the exact fit heater control valve with rear heat and air for your 1996 Chevrolet Suburban 1500 5.7l is currently unavailable online. 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 9/7/2013 by Steve from AAP
          • Q:

            How do I install this? Is there a vacuum hose with it? Where does that attach to the vehicle? Vehicle is a 1996 GMC Yukon, Model K10706 with 5.7L V8 gasoline engine
            Asked on 5/9/2013 by Al from Washington, DC

            1 answer

            • CUSTOMER CARE

              A:

              The Factory Air Heater Control Valve (Part No. 74781) package contains only the heater control valve and does not include gaskets, installation hardware, switch, switch wiring harness. Instructions to replace a heater control valve: 1. Start the engine and allow it to warmup. Turn on the heater. 2. Move the heater temperature switch from cooler to hotter and check for a change in air temperature. 3. Turn off the engine. Open the hood and locate the heater control valve. It is usually mounted to the firewall on the passenger side. 4. Verify that the temperature control cable is connected to the heater control valve and the valve is opening and closing. Check for coolant leaks at the valve. 5. Allow the engine to cool down. 6. Disconnect the control cable from the heater control valve. 7. Disconnect the heater hoses from the heater control valve. 8. Remove the old heater control valve. 9. Install the new heater control valve. 10. Reconnect the heater hoses and the control cable. 11. Refill the radiator and overflow reservoir with coolant. 12. Pressure test the cooling system and check for any leaks. Top off coolant in the radiator. 13. Install the radiator cap. 14. Start the engine and allow it to warmup. Turn on the heater and move the temperature switch from cooler to hotter. Verify that hot air is coming out. 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. 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 5/10/2013 by Steve from AAP
          • Q:

            How do I install this? Is there a vacuum hose line with this? where does that attach?
            Asked on 5/8/2013 by Al from DC

            1 answer

            • CUSTOMER CARE

              A:

              In order to assist you further about Factory Air Heater Control Valve - Part No. 74781, please provide the year, make, model and engine size of your vehicle application or you can contact us directly at 1-877-ADVANCE (238-2623) or visit your nearest Advance Auto Parts store for further assistance.

              Answered on 5/8/2013 by Morgan from AAP
          • Q:

            Is this part also for a Suburban with rear air?
            Asked on 2/5/2011 by Anonymous

            1 answer

            • CUSTOMER CARE

              A:

              For further assistance, please provide the year, make and engine size of your vehicle.

              Answered on 2/8/2011 by David the Dynamite Parts Guy from AAP
          • Q:

            WHERE IS VALVE LOCATED
            Asked on 10/24/2009 by Anonymous

            2 answers

            • CUSTOMER CARE

              A:

              Usually it is near the heater core behind the glove box.

              Answered on 10/31/2009 by Paul from Advance Auto Parts
            • A:

              if you are standing at the front of the truck looking to ward the engine it is located to your left on the inner fender about exhaust manifold level

              Answered on 11/23/2009 by Suburban freak from elko nevada
          Displaying questions 1-5

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