Product Description
MAHLE 55522 is the Grade A multi-layer steel (MLS) cylinder head gasket engineered for the 2017–2023 GM 6.6L Duramax L5P. It’s an OE-quality direct fit with a combustion load limiter for long-term sealing under high cylinder pressures. Sold individually; two required per engine (one per bank).
- Engine: GM Duramax L5P 6.6L V8 (VIN Y)
- Gasket Grade: A (target thickness ~1.20 mm / 0.047” per MAHLE catalog)
- Construction: Multi-Layered Steel (MLS) with combustion load limiter
- Quantity Needed: 2 per engine (left & right banks)
Fitment
- 2017–2023 Chevrolet Silverado 2500HD/3500HD (6.6L Duramax L5P)
- 2017–2023 GMC Sierra 2500HD/3500HD (6.6L Duramax L5P)
Cross Reference & Alternatives
- MAHLE: 55522 (Grade A), 55523 (Grade B), 55524 (Grade C).
- GM OEM Grade A reference: 12727484 (for L5P, Grade A). (Reference only; thickness selection must match piston protrusion.)
- Related set (top end, no head gaskets): MAHLE HS55522.
What’s Included
(1) MAHLE Grade A MLS cylinder head gasket for L5P. Order two for a complete job.
FAQ
How do I choose the correct L5P head gasket grade (A/B/C)?
Per AERA guidance and MAHLE documentation, measure piston protrusion at TDC and select Grade A/B/C accordingly. Grade A targets ~1.20 mm thickness. Always verify protrusion to ensure correct quench and compression ratio.
Is this an MLS gasket and does it include both sides?
Yes—this is a multi-layer steel (MLS) gasket. It’s sold individually; the L5P requires two gaskets (one per bank).
Will it fit all 2017–2023 L5P 2500/3500 trucks?
Yes—application covers 2017–2023 Silverado/Sierra 2500HD/3500HD with the 6.6L Duramax L5P. Always verify VIN and build details before ordering.
Do I need head bolts or studs with this gasket?
New torque-to-yield bolts or quality head studs are recommended whenever the head is removed. Pair with a full top-end set (HS55522) and follow GM/MAHLE torque specs and surface finish requirements for MLS.
