The Advance Adapters 4L80E to Atlas 1.25" Adapter (SKU AS-6408) is a short-format adapter that mates a GM 4L80E transmission to the Atlas transfer case. At 1.25" in length, it's noticeably shorter than the AS-6455 kit, and it's machined from 356-T6 heat-treated aluminum alloy for strength.
Important compatibility note straight from the listing: this adapter is used exclusively with 4L80E 4WD models, and it must be paired with Advance Adapters' 4L80E VSS kit (50-6409), which is sold separately. Without that VSS kit, this adapter alone won't complete the transmission-to-transfer-case signal path — so if you're speccing this swap, budget for both parts together rather than assuming this one adapter covers everything.
What's included:
- Adapter, 4L80 to Atlas, Short (51-6408)
- Bolt, 10mm 1.5 x 35mm SHCS 12.9 Zinc (720028)
This is a lean, purpose-built kit — just the short adapter housing and its mounting bolt. It's the right pick when you need the shorter 1.25" spacing for your particular 4L80E/Atlas combination, but remember to add the 4L80E VSS kit (50-6409) to the cart as well, since Advance Adapters explicitly calls that out as required rather than optional.