This Borla S-Type muffler (60679) replaces the Polyphonic Harmonizer behind the primary muffler in select Borla ATAK cat-back systems for the Chevrolet Silverado 1500 and GMC Sierra 1500 6.2L, dropping the tone to the quieter S-Type level. It is a 3.5in diameter direct-fit muffler built from premium T-304 stainless steel with CNC-accurate construction for maximum flow and power.
| Type | S-Type replacement muffler |
| Sound | S-Type (quieter than ATAK) |
| Diameter | 3.5in |
| Material | T-304 stainless steel |
| Use | Swaps into select Borla GM truck ATAK systems for S-Type sound |
| Part Number | 60679 |
| Warranty | Million-Mile Warranty |
Documents: Installation Instructions (PDF)
This part fits:
| Year | Make | Model | Submodel |
|---|---|---|---|
| 2020-2021 | Chevrolet | Silverado 1500 | Custom Trail Boss |
| 2019-2026 | Chevrolet | Silverado 1500 | High Country |
| 2020-2026 | Chevrolet | Silverado 1500 | LT Trail Boss |
| 2019-2026 | Chevrolet | Silverado 1500 | LTZ |
| 2020-2026 | Chevrolet | Silverado 1500 | RST |
| 2022-2026 | Chevrolet | Silverado 1500 | ZR2 |
| 2019-2026 | GMC | Sierra 1500 | AT4 |
| 2022-2026 | GMC | Sierra 1500 | AT4X |
| 2019-2026 | GMC | Sierra 1500 | Denali |
| 2022-2026 | GMC | Sierra 1500 | Denali Ultimate |
| 2019-2026 | GMC | Sierra 1500 | SLT |
Shipping: In-stock orders placed before 3 PM EST ship the same day, and everything else ships within 24 hours. Standard, expedited, and overnight options are available at checkout. Backordered items ship as soon as we get them back in stock. Contact us for lead times. See the full Shipping Policy.
Returns: 30-day returns on new, unused items in original packaging. See the full Refund Policy.
