B&M 20234 Adjustable Vacuum Modulator

(812 Reviews)

Price
$23.92

Quantity
(10000 available )

Total Price
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18 Ratings
16
2
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Reviews
  • Steven Justice Jr

    07-06-2025

    Great product

  • Frank

    > 3 day

    great item fo the price, than you.

  • Blue & Silver

    > 3 day

    Works as it should.. Great job

  • Charlie swoboda

    > 3 day

    Easy to adjust and let me set the shifting where I wanted it

  • Stone

    > 3 day

    It worked as advertised.

  • Brad

    > 3 day

    Through this in a used transmission and works fine so far. Bought this one for the name behind it.

  • the starfish

    > 3 day

    I bought this to replace a leaky modulator on my 1976 GMC motorhome with a THM425 and 455ci Toronado engine. The shift points were perfect out of the box, no adjustments needed.

  • Mary

    Greater than one week

    Worked great....

B&M accessories help you complete your project with parts designed and selected by the experts at B&M. This vacuum modulator comes pre-adjusted for "normal" shift points, but it is fully adjustable, allowing you to customize the shift points (within a range of 2-4 mph). This unit is designed for use with select applications, including GM TH400 and TH350 transmissions. Please note: If you have a big camshaft and your engine does not make adequate vacuum, you will not be able to make the stock or B&M modulator work properly, usually resulting in late, hard shifts.

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