Skip to main content


Quadratrac Control Diaphragm

Part Number:
Calculated at Checkout

Have a Question? Ask a product expert! Call or Text 253-320-7604

Product Details

We have a replacement Quadratrac Diaphragm available again!!!   These are machined out of billet aluminum and are fully rebuildable, and have a brand new diaphragm!   This is the transfer case mounted control vacuum diaphragm for switching in and out of 'Emergency Drive'.

** You must remove the yoke to fit this unit and then replace the yoke when it's installed **

Made in USA!

Original Part Number: 8122991 / J8122991

  • Fits All with QT Transfer Case (Full Size Jeeps, CJ's etc)
  • Fully Rebuildable
  • New Diaphragm
  • Made in the USA!

Reviews (1)

  • Emergency drive control diaphram

    Posted by Unknown on Mar 16th 2023

    Does this part fit as the original one