2023 Grand Design Reflection 315RLTS Black Tank 28x58x8.5 with 3" End Drain

The dimensions identify a tank family to investigate, not a confirmed fit for a 2023 Grand Design Reflection 315RLTS. ICON's current catalog, printed page 149, lists HT176B-ED as a center-end-drain holding tank with a 58 × 28 × 8½-inch footprint and 43 US gallon capacity. That matches the stated envelope when length and width are put in the same order; it does not prove the inlet, vent, drain or mounting arrangement matches this RV.

The catalog distinguishes four configurations: 12378 has a 3-inch spigot and four sensors; 14311, 14312 and 14694 are listed as replacements for Jayco references 0335791, 0335792 and 2007856 respectively. The current ERVP HT176B-ED listing is native SKU 14694 / reference 2007856. Do not transfer the generic 12378 configuration to 14694 or assume that a Jayco cross-reference establishes Grand Design fit.

Compare the original tank's complete part number and drawing with the exact supplied configuration. Check body shape and taper, mounting flange/supports, usable clearance including projecting fittings, drain centerline and connection type, and every toilet inlet, vent and sensor location measured from consistent reference edges. “3-inch end drain” alone does not locate those openings or establish a direct connection.

The earlier guaranteed-fit statement is withdrawn. Obtain an exact drawing or documented original-part cross-reference before selecting a replacement. HT176B-ED remains a dimensional candidate; this page does not confirm a drop-in replacement, authorize moving fittings or establish that a particular configuration is available to order.