Automatic Transmission Vacuum Modulator
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Pro-King Automatic Transmission Vacuum Modulator

Part No. MD-28 Warranty  

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Fully adjustable vacuum modulator to maintain accurate shift points.
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O.E.M. Replacement:Yes
Transmission Manufacturer:GM
Transmission Model:250/C; 350/C; 440-T4 (4T60); 4T60E

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by PowerReviews
Pro-KingAutomatic Transmission Vacuum Modulator
 
4.5

(based on 2 reviews)

Ratings Distribution

  • 5 Stars

     

    (1)

  • 4 Stars

     

    (1)

  • 3 Stars

     

    (0)

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    (0)

  • 1 Stars

     

    (0)

Reviewed by 2 customers

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Displaying reviews 1-2

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5.0

great universal modulator made in N.C.

By shorty cadalac man

from asheville nc

About Me Mechanic

Pros

  • Durable
  • Easy To Use
  • High-Performance
  • Lightweight
  • Versatile

Cons

    Best Uses

    • Large Cars
    • Replaces Larger Units
    • Small Cars
    • Trucks

    Comments about Pro-King Automatic Transmission Vacuum Modulator:

    my modulator was larger diameter but this modulator
    fit and worked perfect i was impressed it was made
    in N.C.

    • Was this a gift?:
    • No

    Comment on this review(earn points)

    (10 of 19 customers found this review helpful)

     
    4.0

    simple

    By jgor

    from st cloud FL

    Pros

    • Easy To Use
    • Lightweight

    Cons

    • Which setup

    Best Uses

    • Any 34L GM
    • Large Cars
    • Small Cars
    • Trucks

    Comments about Pro-King Automatic Transmission Vacuum Modulator:

    easy as putting gas in your car

    • Car & Truck:
    • Auto Enthusiast, Casual Driver, Shade Tree Mechanic, Truck Enthusiast

    Comment on this review(earn points)

    Displaying reviews 1-2

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    Do you have questions about this product?(earn points for answers!)

     

    Ask a question, get answers from real customers and in-house experts. Or contact Customer Care by email or call 1-877-238-2623.

    21 Questions | 25 Answers
    Displaying questions 1-10Previous | Next »
    • Q:

      Where can I get direction on adjusting this modulator? The one that bought did not have any directions on adjusting it.
      Asked on 3/25/2013 by Wesley

      1 answer

      • CUSTOMER CARE

        A:

        For further assistance regarding Pro-King Automatic Transmission Vacuum Modulator, Part No. MD-28, please provide the year, make, model and engine size of your vehicle. This information would help us to assist you in a better way.
        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 3/26/2013 by Aaron from AAP
    • Q:

      2004 Impala 3.4L - wont go into Drive or Reverse until the car warms up. Found online that a Ford truck owner was able to fix his problem by getting a flush, new filter, and replacing the vacuum. Thoughts? Also, is this a DIY job?
      Asked on 2/15/2013 by Scott from Wooster, OH-IO

      2 answers

      • A:

        Change to synthetic and change the filter. The modulator probably won't have anything to do with it but the other will likely solve it, for a while.

        Answered on 1/10/2014 by kansas bonneville from shawnee ks
      • CUSTOMER CARE

        A:

        With reference to your inquiry on the Pro-King Automatic Transmission Vacuum Modulator -part# MD-28, without the presence of the vehicle we could neither diagnose the problem nor provide you with a 100% answer. However, I would suggest taking your vehicle to a certified mechanic for a proper diagnosis before buying and having parts installed that may not (solve/be) the problem. For any further assistance, you may also 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 2/16/2013 by Vincent from AAP
    • Q:

      my car will not shift into overdrive
      Asked on 1/10/2013 by mike

      1 answer

      • CUSTOMER CARE

        A:

        Sorry, without the presence of your vehicle we would not be able to properly diagnose it nor provide you with a 100% answer. We would suggest that you take your vehicle to a certified mechanic for further diagnosis. For further assistance, please feel free to call us at 1-877-238-2623 or visit your nearest Advance Auto Parts store and one of our representatives would be more than happy to assist you.

        Answered on 1/11/2013 by Steve from AAP
    • Q:

      I would like to know if this part will fit my 2002 grandprix pontiac se 3.1 and where is it located.
      Asked on 11/27/2012 by kw from Maryland

      1 answer

      • CUSTOMER CARE

        A:

        This Pro-King Automatic Transmission Vacuum Modulator (Part No. MD-28) is an exact fit for your 2002 Pontiac Grand Prix SE. The vacuum modulator should be bolted to the front side of the transmission, approximately three-fourths of the way to the top of the transmission. For further assistance, please feel free to call us at 1-877-238-2623 or visit your nearest Advance Auto Parts store and one of our representatives would be more than happy to assist you.

        Answered on 11/27/2012 by Steve from AAP
    • Q:

      2000 pontiac grand prix 3.8L naturaly asperated symptoms: Shifts late- engine rpm eratic at times- stalls and then restats. Sounds like vacuume leak right? No sign of leak on hoses and checked with spray around critical areas.....Nothing....Any Ideas????
      Asked on 8/22/2012 by Ozman from Bemidji,Mn

      1 answer

      • CUSTOMER CARE

        A:

        Yes, there may be a vacuum leak. However, without the presence of your vehicle we would not be able to properly diagnose it nor provide you with a 100% answer. We would suggest that you take your vehicle to a certified mechanic for further diagnosis.

        Answered on 8/22/2012 by Steve from AAP
    • Q:

      I have noticed and read in some forums that the different color bands on these modulators determin the type of shifts they produce. Which color would give you softer shifts. Also when adjusting screw the clockwise does it give you firmer or softer shifts. 1998 Chevy Lumina Base 3.1 L
      Asked on 7/19/2012 by Jason from Lima, OH

      1 answer

      • CUSTOMER CARE

        A:

        As per Pro-King the Pro-King Automatic Transmission Vacuum Modulator (Part No. MD-28) comes in the color - Universal Red Stripe. This code fits all the following transmissions: 250/C, 350/C, 400 (3L80), 4T60E, TH425. For any further assistance please feel free to call us at: 1-877-238-2623 or visit the nearest Advance Auto store and one of our representatives will gladly assist you with any questions or concerns you may have.

        Answered on 7/20/2012 by John the Car-Doc from AAP
    • Q:

      How do you adjust for softer shifts. 1998 chevy Lumina 3.1L
      Asked on 7/8/2012 by jason from lima, ohio

      1 answer

      • CUSTOMER CARE

        A:

        The transmission vacuum modulator valve determines how much load is on the engine so the transmission can shift properly. It has a vacuum line that connects to the intake and measures the amount of vacuum in the engine. Remove the vacuum hose from the modulator. Using a small screwdriver, turn the screw inside the modulator. Vacuum should measure 13-17 at the modulator idling hot in drive brakes applied. It may take several tries to get it right. For any further assistance, please visit your nearest Advance Auto store or call us directly at 1-877-ADVANCE (238-2623) and one of our representative there would be more than happy to assist you.

        Answered on 7/9/2012 by Vincent from AAP
    • Q:

      my 2004 chevy venture transmission wants to jerk a little when taking off from stop. n going into the next higher gear. would this be the modulater? thanks
      Asked on 4/21/2012 by Harry from 37862

      1 answer

      • CUSTOMER CARE

        A:

        The transmission modulator valve may be the possible cause of the problem. However, I would suggest taking your vehicle to a certified mechanic for a proper diagnosis before buying and having parts installed that may not (solve/be) the problem.

        Answered on 4/22/2012 by Vincent from AAP
    • Q:

      Have a 2000 Impala having troubles goin fromm 1st to 2nd will this help or maybe change filter and fluid. Thank you
      Asked on 3/27/2012 by Rich from Weston, WV

      2 answers

      • CUSTOMER CARE

        A:

        This could possibly be the problem. However, without the presence of your vehicle we would not be able to properly diagnose it nor provide you with a 100% answer. We would suggest that you take your vehicle to a certified mechanic for further diagnosis.

        Answered on 3/28/2012 by Steve from AAP
      • CUSTOMER CARE

        A:

        The Transmission Vacuum Modulator and or even the transmission power control solenoid may be the problem. However, I would suggest taking your vehicle to a certified mechanic for a proper diagnosis before buying and having parts installed that may not (solve/be) the problem.

        Answered on 3/28/2012 by Vincent from AAP
    • Q:

      I have a 2002 chevy venture would anybody know where the trans modulator would be?
      Asked on 9/18/2011 by ron from new york

      1 answer

      • CUSTOMER CARE

        A:

        Generally, the modulator is attached to the outside of the transmission case and has a shaft which passes through the case and attaches to the throttle valve in the valve body.

        Answered on 9/18/2011 by Vincent from AAP
    Displaying questions 1-10Previous | Next »

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