Mega Flush ~ 3-in-1 System Cleaner

Mega Flush


Castle® Mega Flush™ is a safe, effective product designed to internally clean varnish build-up and other deposits from valve body, filter screen, and other internal parts of the transmission. It will prepare transmission for new fluid and a fresh start. Safe to use with all conventional transmission fluids, full synthetic and synthetic blends.


  • For use with automatic transmissions.


1. Run vehicle in park for 10 minutes.
2. Add one bottle of Castle® Mega Flush™ through transmission fill tube.
3. Raise vehicle so that wheels are off floor.
4. Shift vehicle selector to all positions.
5. Drain transmission and replace filter. Add new fluid plus a bottle of Castle® TC-12 Transmission Conditioner™ .


  • 8 oz (#C0826) 24/case
  • 1 gal (#C12826) 4/case
  • 5 gal (#C0826-5) pail


Store away from heat source.

Product #:

C0826, C12826, C0826-5

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U.S. Customers
Castle AutoChem Products Ltd services Canadian customers only.

U.S. customers, please visit the Castle U.S. Website,
or call 1-800-876-0222.