1. Product Overview
The KOHLER K-6428-58 Memoirs Stately Comfort Height Skirted One-Piece Elongated Toilet combines elegant design with efficient performance. Inspired by architectural aesthetics, this toilet features crisp lines and a stately design. It is engineered for water savings without compromising flush power, utilizing a 1.28 gallons per flush (GPF) system. The Comfort Height feature provides chair-height seating for enhanced accessibility, and the included quiet-close seat ensures silent operation and easy cleaning.

Figure 1: A front-side view of the KOHLER K-6428-58 Memoirs Stately one-piece toilet in Thunder Gray, showcasing its elegant, skirted design.
2. Key Features
- Compact Elongated Bowl: Offers increased comfort while maintaining a compact footprint, similar to a round bowl.
- Comfort Height Seating: Provides a chair-height seating position, facilitating easier sitting and standing for most adults.
- AquaPiston Flush Technology: The canister design allows water to enter the bowl from all sides (360 degrees), enhancing flush power and effectiveness.
- Water Efficiency: A 1.28 GPF flush system contributes to significant water savings annually compared to standard 3-gallon toilets.
- Durable Canister Design: Features 90% less exposed seal material than traditional 3-inch flappers, promoting long-term, leak-free performance.
- Quiet-Close Seat: Includes a Glenbury quiet-close seat with Grip-Tight bumpers for silent closing and stability.
- Left-Hand Trip Lever: Equipped with a polished chrome left-hand trip lever for convenient flushing.

Figure 2: An illustration comparing a standard toilet height (15 inches) with a Comfort Height toilet (16+ inches), demonstrating how Comfort Height makes sitting and standing easier.

Figure 3: An internal view of the toilet tank, highlighting the AquaPiston canister flush valve, which allows water to flow into the bowl from all sides for powerful flushing.

Figure 4: The WaterSense logo, signifying that the toilet meets EPA criteria for water efficiency, conserving water without compromising performance.
3. Setup and Installation
This one-piece toilet is designed for floor-mounted installation. For optimal performance and to ensure proper sealing and functionality, professional installation is highly recommended. The product includes the toilet unit, necessary hardware, a detailed installation guide, the toilet seat, and the trip lever. A supply line is not included and must be purchased separately.
3.1 Pre-Installation Checklist
- Verify all components are present as listed in the packaging.
- Ensure the floor is level and the plumbing connections are ready.
- Read the complete installation guide thoroughly before beginning.

Figure 5: The KOHLER Memoirs Stately toilet in Thunder Gray, elegantly installed in a modern bathroom setting, highlighting its aesthetic integration.
4. Operating Instructions
The KOHLER K-6428-58 toilet operates with a simple and efficient flushing mechanism.
4.1 Flushing the Toilet
- Ensure the water supply valve is fully open.
- Press down firmly on the polished chrome left-hand trip lever located on the front of the tank.
- The AquaPiston canister will lift, allowing water to flow into the bowl from all sides for a powerful and complete flush.
- Release the trip lever. The tank will refill automatically.
4.2 Using the Quiet-Close Seat
The included Glenbury quiet-close seat is designed to prevent slamming. Simply push the seat or lid down gently, and it will lower slowly and silently on its own. The Grip-Tight bumpers help hold the seat firmly in place.
5. Care and Maintenance
Proper care and maintenance will ensure the longevity and appearance of your KOHLER toilet.
5.1 Cleaning the Toilet
- Use mild, non-abrasive cleaners for all surfaces. Avoid harsh chemicals, abrasive pads, or scouring powders, as these can damage the finish.
- For the ceramic surfaces, apply a toilet bowl cleaner and scrub with a soft brush. Rinse thoroughly after cleaning.
- Wipe down the exterior surfaces, including the tank, bowl, and base, with a soft cloth dampened with a mild cleaning solution.
- For the seat, use a soft cloth and mild soap and water. Do not use harsh chemicals on the seat.
5.2 Internal Mechanism Maintenance
The AquaPiston canister flush valve is designed for durability and minimal maintenance. Its robust construction with less exposed seal material reduces the likelihood of leaks. Periodically inspect the internal components for any signs of wear or debris. If issues arise, consult the troubleshooting section or contact customer support.
6. Troubleshooting
This section addresses common issues you might encounter with your toilet. For complex problems, it is recommended to contact a qualified plumber or KOHLER customer service.
6.1 Toilet Not Flushing Properly
- Check Water Supply: Ensure the water supply valve behind the toilet is fully open.
- Inspect Trip Lever: Verify the trip lever is connected correctly to the AquaPiston canister and is not obstructed.
- Water Level: Check the water level in the tank. It should be at the fill line indicated inside the tank.
6.2 Continuous Running Water
- Check Fill Valve: Ensure the fill valve is not stuck open or improperly adjusted.
- Inspect Canister Seal: The AquaPiston canister seal might be obstructed by debris or require replacement if worn.
- Float Adjustment: Verify the float mechanism is not set too high, causing water to continuously overflow into the overflow tube.
7. Technical Specifications

Figure 6: A diagram illustrating the key dimensions of the KOHLER Memoirs Stately toilet, including total height, width, bowl height, and length, with a standard 12-inch rough-in.
| Specification | Detail |
|---|---|
| Model Number | K-6428-58 |
| Color | Thunder Gray |
| Product Dimensions (D x W x H) | 28.75" x 17.63" x 3.15" |
| Material | China (Toilet), Plastic (Seat) |
| Item Weight | 114.5 Pounds |
| Installation Type | Floor Mounted |
| Shape | Elongated (Oval) |
| Water Consumption | 1.28 Gallons per Flush (GPF) |
| Flush Type | Gravity Flush (AquaPiston Technology) |
| Certification | WaterSense |
| Included Components | Toilet, hardware, installation guide, toilet seat, trip lever |
| UPC | 885612382320 |
8. Warranty and Support
KOHLER products are manufactured to high standards of quality and performance. Specific warranty details for the K-6428-58 Memoirs Stately toilet are typically included with your product packaging. Please refer to the documentation provided at the time of purchase for comprehensive warranty information.
For technical assistance, replacement parts, or further inquiries, please contact KOHLER customer support. You can find contact information on the official KOHLER website or within your product's documentation.
For additional resources and product information, visit the official KOHLER Store on Amazon.





