Silent Fill Toilet Valve Kit, Genuine Part GP1138930, Adjustable with Multiple Fill-Rate Inserts

The Kohler Silent Fill Toilet Valve Kit is a reliable replacement part that made fixing my toilet much easier. It’s designed to replace an old or worn‑out fill valve on Kohler toilets, and the “silent fill” feature noticeably reduces the usual rumbling or loud refill noise after flushing. Installation was straightforward — I followed the instructions, and it fit well without any complicated plumbing tools. The height is adjustable so it can match the tank’s water level properly, and the adjustment helped me get the right fill rate easily. As an OEM (original equipment manufacturer) part, it feels solid and durable. Most users report that it works quietly and reliably after installation, though there are occasional reports of adjustment being a little tricky at first. Bottom line: If your toilet is noisy, runs constantly, or isn’t filling right, this silent fill valve kit is a practical and affordable way to restore smooth, quiet performance. Great value for a basic but essential toilet repair part.

My original Kohler GP1138930/400a lasted nearly 25 years - amazing longevity. I knew it was dying a slow death when I would hear it fill by itself at night and running long after flushing. I ordered this new valve from Amazon about a week ago. The valve finally quit last night and I shut the water to the toilet off and fixed it today. When I removed the 25 year old fill valve today and compared it to the new one, it was nearly a dead ringer. The major change that jumped out was that the former valve had a metal float adjustment rod had been changed to a threaded plastic screw rod which is actually far easier to adjust than the previous version. One thing to know is that this new valve is expandable in length to almost 14" from the inside of the tank to the valve top simply by twisting the threaded gray valve stem. It was exactly the same setup on the 25 year old valve and I just matched the length because there are 1" increments on the gray stem up to 13" and the original was set at 13". So take note of those little details if you are replacing the same valve and save some time and aggravation The new valve comes with a variety of color coded water restrictors that go on the output hose. The original valve didn't have any of these restrictors in place so I didn't use them and the valve worked great but your situation may vary. There are some helpful installation videos on YouTube if you Google "replace Kohler 400a toilet tank valve" and go to videos. I'm very handy around the house and was a diesel and auto mechanic decades ago after college to bank some $$ prior to going back to college for pharmacy school. I can fix almost anything but plumbing always seems to be my Achilles heel, even as a diesel mechanic - hydraulic lines can be a real pain. In home plumbing, there's always a leak, a missing part, some tool I don't have, something I over tighten and break or under tighten and it leaks or the inevitable hardware store trip(s). The new valve was simple to install, didn't leak, required very common hand tools and I only made one trip to the hardware store for a new 12" stainless supply line. If I'm changing the valve, I may as well change the supply line as well, The new Kohler valve is simple to adjust for fluid flow, shutoff height and actual installation. As I mentioned, plumbing never seems to go well for me despite the fact that I can wire outlets and ground faults, light fixtures, AC units and hot tubs, install drywall, do flawless custom finish/trim work and install any sort of interior door. But my plumbing skills simply suck. So this valve MUST be easy to install if a plumb-tard like me can get it done in under an hour. I realize some folks have zero ability in this area and that's plumbers make 6 figures a year because they earn it by being really good at work that annoys others to death. If you are one of those folks, dial up your local plumber and be ready to donate $100 - $150+ for this repair. I just ordered two more of these valves, new USA made 12" stainless flex water lines and new Kohler flush handles from Amazon for my other two toilets in the same house. If one valve died after nearly 25 years, the other two have to be close to failure as well so I may as well change them all out after beating the learning curve, while my plumbing luck holds out and before the other old ones crap out - pun intended. Photos: I added some photos. The left hand photo shows the my 25 year old Kohler/Fluidmaster 400a next to the new one from Amazon. The new one has been extended by holding the gray stem and twisting the black stem to it's max length for my installation - yours may vary. The middle photo shows the removal of the small blue metering jet from the new valve. My original valve had no metering jet installed and I followed suit. Again, your situation may vary. The far right photo shows one of the weak points of the new valve. The black tube is new and is included in the kit along with the little metal squiggle annotated by the red arrow. That metal squiggle is supposed to hold the fill hose in the plastic fill pipe in the toilet tank. The old fill tube hardware annotated by the yellow arrow is the original set up that I cleaned up with CLR and reinstalled. The new metal squiggle just didn't work for me and could be a 1 star deduction in some customers eyes. New isn't always better.

Just installed in our guest toilet Very easy to do and works great. Same price at Kohler so buy on Amazon and get it faster.

Replaced my old, tired fill valve with this Kohler kit and couldn’t be happier. I’ve got an older Santa Rosa one-piece, and this fit perfectly—no modifications, no guessing, just dropped right in like it was meant to be there (because it was). The difference was immediate: the tank fills quickly and, more importantly, quietly. No more hissing, wheezing, or sounding like my toilet is trying to launch into orbit every time it refills. Now it’s so quiet I actually had to double-check it was working the first time. Install was straightforward and took maybe 10minutes, even taking my time. Everything lined up exactly as expected, which is always a nice change from “universal” parts that are anything but. For the price, this is a no-brainer. Solid build, perfect fit, and it actually makes the toilet feel like new again. Highly recommend—your ears (and your bathroom) will thank you.

Valve works fine a this moment. But company does not provide very important o ring seal. Every time you replace this valve, o ring must be replaced. But no o ring in hardware.

Took about 4 minutes to install. Works perfectly. If you have a Kohler toilet, don’t waste your time on less expensive alternate brands. The few dollars you save won’t be worth it, since cheaper ones tend to leak or not flush properly. Make sure you get the right model with either a gray or black shank, but you can easily figure that out from the Kohler website.

Much better than Fluidmaster or Korky Universal kits. This original parts manufacturer produces SILENT valves. Much much better than the universal kits from Lowes or Home Depot. Don't waste your time with competitors, opt for Kohler for your Kohler or Sterling manufactured toilers!

Works quite well. Easy to install.

The connector (7/8 ballcock) is special and not listed in the documentation. In Singapore this is not common and I had to order an special braided hose with the correct connector. But the fill valve is well built, easy to adjust the fill levels from the top knob.

lasted 6 weeks

Repuesto original, precio bajo, excelente calidad, instalación facil, sin herramientas. Funciona perfecto.

Works Great. Easy to install. No leaks

Lo utilicé en un sanitario de otra marca y le quedó a la perfeccion. El proceso de instalacion es sumamente facil, en 10 minutos ya está funcionando