Bosch 6091C HEPA Cabin Air Filter

The 6091C is a three-layer filter: a spunbound polyester pre-filter, a meltblown electrostatic core, and a static cotton layer Bosch adds to increase particulate capacity. That media stack is consistent with HEPA-grade construction; Bosch's HEPA cabin-filter category page cites ISO 29463-3 and 99.97% at 0.3 microns, though that efficiency claim is published at the product-line level — no independently-published lab result for this specific part number was located as of 2026-05-13. There is no activated carbon layer, so odors and volatile compounds pass through unimpeded. Fitment spans the GM family: Silverado, Traverse, Colorado, Buick Encore, several Cadillac crossovers, and others. The 8.3" × 9.7" × 1.4" unit installs behind the glovebox without special tools; community reviewers consistently report a precise, force-free fit. Rated 12-month / 12,000-mile service interval; one verified-purchase reviewer reports intact media at two years of use.

The right pick for owners of GM trucks and crossovers listed in the fitment guide who want HEPA-grade particulate filtration above the OEM-equivalent baseline — fitment is precision-confirmed across multiple platforms and model years in community reviews, and the multi-layer meltblown media is consistent with the HEPA-grade efficiency tier. Skip if your vehicle is not on the confirmed fitment list — an incorrect filter leaves bypass gaps that negate any filtration benefit. Skip if you need odor control or VOC reduction — this filter has no activated carbon layer; a filter with a carbon composite layer (such as the FRAM TrueGUARD series for GM fitments) addresses odors at a comparable price point. Also skip if you require independently-verified submicron filtration certification — Bosch's HEPA claim cites ISO 29463-3 on Bosch's own brand page; no independently-published test results traceable to part number 6091C were located.

Passive synthetic-media replacement filter — multi-layer meltblown polypropylene and polyester construction with no chemical exposure pathway during installation; no SDS exists or is required. All-synthetic media construction (meltblown polypropylene, spunbound polyester, foam seal) is landfill-bound at end of service — no recyclable frame component was confirmed from the available spec; 12-month replacement generates one spent filter unit per year per vehicle.