Identifying Tempered vs. Acoustic Glass on Your Optima
Determining the exact door window installed in your car comes down to checking whether your vehicle uses solid tempered glass or dual-layer acoustic laminated glass. You can confirm this immediately by examining the manufacturer bug etched in the bottom corner of your roll-up window or by rolling down the pane and running your fingernail over the top edge. If you see two sheets of glass sandwiching a vinyl interlayer with a subtle ridge at the top, your vehicle has acoustic glass; a smooth, rounded single pane denotes standard 70% solar green-tinted tempered glass.
Most EX and SX trims built on the TF platform use single-layer tempered windows, corresponding to standard industry catalog numbers FD24943 for the front left driver pane and FD24942 for the front right passenger pane (factory replacement part numbers 82411-2T010 and 82421-2T010 respectively). Higher-tier trims and hybrid editions often run the acoustic laminate specification. Because I exclusively supply aftermarket door glass from manufacturers like Pilkington, PGW, FYG, and XYG, I match the optical clarity, edge curvature, and tint percentage of these variants without using dealer-branded units.
Frame Design and Rear Division Bar Components
These cars use a framed door architecture with rigid upper window run channels rather than a frameless setup. On the rear doors, Kia opted for a split-window configuration consisting of the drop-down movable pane and a stationary rear quarter vent glass, separated by an upright metal division bar.
| Glass Location | OEM Part Reference | Standard Catalog Number |
|---|---|---|
| Front Driver (LH) | 82411-2T010 | FD24943 |
| Front Passenger (RH) | 82421-2T010 | FD24942 |
| Rear Left Movable (LH) | 83411-2T010 | FD24945 |
| Rear Right Movable (RH) | 83421-2T010 | FD24944 |
| Rear Left Vent (LH) | 83417-2T010 | FV24947 |
| Rear Right Vent (RH) | 83427-2T010 | FV24946 |
The roll-down glass connects to the window regulator mechanism using specialized clamp grips and bushings (OEM prefix 82412 and 83412). Unlike vehicles that use plastic push-pins that can pop free, this setup bolts directly through factory-formed holes in the bottom edge of the glass. In addition, parts can vary slightly depending on whether your car was assembled at the West Point, Georgia plant or imported directly from South Korea, which altered specific interior weatherstrips and carrier assemblies.
Window Carrier Mechanics and Cable Snags
The window lifting system relies on a composite carrier plate that seals the inner door frame. When windows fail to move or drop sideways inside the door shell, the culprit is often a snapped plastic Bowden cable pulley inside this inner module rather than an issue with the glass itself. If the glass drops loose into the door cavity, the bolted connection point or the carrier's drive cable has usually let go.
Post-Replacement Inspection Checklist
Once your new door glass is seated and secured, verify these specific functional points before driving:
- Confirm the front and rear edges of the drop glass seat squarely into the vertical rubber channels without binding or pinching as the window approaches the top frame.
- Test the automatic up-and-down function to ensure the pinch-protection sensor does not falsely detect resistance and reverse the motor.
- Inspect the exterior beltline weatherstrip along the bottom edge of the window frame to verify it sits completely flat against the outer glass face to stop water intrusion.
- On the rear doors, confirm the vertical division bar seal sits tight against both the movable roll-up glass and the fixed stationary quarter vent glass.
