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    • TCI Adjustable Vacuum Modulator Valve | GM Powerglide | 280001
    • TCI Adjustable Vacuum Modulator Valve | GM Powerglide | 280001
    • TCI Adjustable Vacuum Modulator Valve | GM Powerglide | 280001
    • TCI280001.jpg

    TCI Adjustable Vacuum Modulator Valve | GM Powerglide | 280001

    Vendor: TCI Automotive
    Part Number: 280001
    Regular Price $35.95

    Currently out of stock.

    Not sure it fits your vehicle?
    Email sales@berryperformancesales.com with your year, make, model and engine, and we'll help you check fitment before you order.
    Fast Fulfillment: In-stock orders typically ship within 1 to 2 business days.
    Free Shipping on Orders Over $99 | Excludes freight shipments
    International Shipping Available: email sales@berryperformancesales.com for a quote.
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    This TCI adjustable modulator valve is designed specifically for GM '63-'73 Powerglide transmissions. The vacuum modulator signals engine load so the transmission can set the proper line pressures and shift points, and worn modulators can cause drivability problems or premature failure. This new adjustable unit renews performance and allows part-throttle shift points and line pressures to be raised or lowered slightly by turning the screw inside the vacuum nipple.

    • Fits GM '63-'73 Powerglide transmissions
    • Adjustable part-throttle shift points and line pressure
    • Set by the screw inside the vacuum nipple for more or less diaphragm pre-load
    • Replaces worn, leaking or ruptured stock modulators
    • For the TH350/400 valve, see 350001
    • Part number: 280001

    FAQ

    What transmission does the TCI 280001 modulator valve fit?

    It is designed for GM '63-'73 Powerglide transmissions.

    What can be adjusted with the 280001 modulator valve?

    Part-throttle shift points and line pressures can be raised or lowered slightly using the screw inside the vacuum nipple.

    Is there a version for the TH350 or TH400?

    Yes. The TH350/400 valve is available under part 350001.

    Shipping Policy
    • Free shipping on orders over $99 (excludes freight shipments).
    • In-stock orders typically ship within 1 to 2 business days. Weekend and holiday orders are processed the next business day.
    • Orders ship from Defiance, Ohio and a nationwide network of warehouses and manufacturers.
    • Items showing an ETA are not in stock yet. ETAs come from the manufacturer and can change.
    • No P.O. Boxes. International orders need a shipping quote, so email us first.

    Read the full Shipping Policy

    Return Policy
    • 30-day return window from the ship date. Returns must be approved first; email sales@berryperformancesales.com with your order number.
    • Items must be unused, complete and in the original packaging.
    • A 20% restocking fee applies, and return shipping is paid by the buyer.
    • Not returnable: installed or modified parts, opened or used programmers and tuners, custom orders, Open Box, and Clearance or Final Sale items.
    • Damaged, defective or incorrect items must be reported within 48 hours of delivery with photos.

    Read the full Return Policy

    Disclaimer

    All products are sold for off-road use only unless otherwise specified. Buyer assumes all responsibility for installation and operation. Seller is not liable for any incidental, indirect, or consequential damages — including engine failure, labor costs, or vehicle downtime — resulting from the use of any product sold.

    By making a purchase from Berry Performance Sales, you acknowledge and agree to abide by the terms and conditions of these Policies.

    For any questions or concerns, please contact us — we’re always happy to help.

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