Water Softeners and Air Filtration Systems - Kinetico

Hi:
I have a Kinetico unit I bought at an auction to replace my faulty Kinetico unit. I got it installed, worked great for awhile, started to "stick", and I have a large pre-filter inline. It has a #4 disc in the metering head. Will changing the metering dice to a #3 disc reduce the amount of water needed to back flush the beds? Looking at metering disc - Will both need to be changed to keep a "matched set" in the metering head?
(I can swap metering disc out of old unit to new one)
Thank you.
Bill

Changing The Metering Disc From A 4 To A 3 Will Increase The Number Of Gallons Between Regenerations...as Far As A "matching Set" I'm Kinda Unclear About That.....what Exactly "malfunctioned" To Cause You To Buy One From An Auction?

Thanks for the info. The unit I had, was draining when regeneration was completed. I am on a well, and the pump kept coming on due to the "leakage" - It (the conditioner) would not fully shut off and the drain line would build line pressure if I held my finger on the drain tube.
The disc in question, top disc has the code #3 or #4 on it, but a second disc is located below it. This bottom one has "cam" detail on the bottom. I was going to put the #3 disc in , but was not sure if I should also swap out the second bottom disc or just replace the top numbered disc.
Thanks for your help.
Bill

Only Swap Out The Meter Disc From The 4 To The Three.....hate To Be The Bearer Of Bad News, But Your Running At The Drain Problem Is Normally Corrected Without Parts Replacement Or Very Minimal