MAHLE CS54580 Lower Engine Gasket Set (2001-2007 6.6L Duramax)

Fitment

Fits the 6.6L Duramax in 2001-2007 Chevrolet Silverado 2500HD and 3500 and GMC Sierra 2500HD and 3500 pickups. That covers the LB7 (2001-2004), the LLY (2004.5-2005) and the LBZ (2006-2007 Classic). MAHLE's Medium Duty Diesel Product Listing places CS54580 under the 6.6L GM Duramax truck 2500 and 3500 with VIN code 1 (LB7), VIN code 2 (LLY) and VIN code D (LBZ).

Check the 8th digit of your VIN before you order. Early 2006 trucks can carry a 2 (LLY) with LBZ hardware, and both D (LBZ) and 6 (LMM) show up in 2007, so 2007 engine parts get split by VIN. This listing is for pickups; do not assume it fits a Kodiak or TopKick medium-duty truck. Verify fitment by VIN or call us.

Why this part

On these engines, bottom-end trouble is mostly a tuned-truck problem. On the LB7, above roughly 550-600 rwhp pistons can crack, head gaskets fail and rods bend. The LLY's rods are on borrowed time past about 600 rwhp, and some put the risk at 500 whp and up. LBZ cast aluminum pistons crack along the wrist-pin centerline once power passes roughly 550-650 wheel horsepower, while stock trucks are rarely affected.

For the LBZ, the catalogued bottom-end rebuild parts include MAHLE replacement pistons with rings in .030 and .040 oversize, heavy-duty rod bolts and main studs. Whatever sends the engine in for bottom-end work, it needs new lower gaskets when it goes back together. MAHLE codes its CS sets as lower sets and its HS sets as upper head gasket sets, so CS54580 is the bottom-end piece of the job.

What you get

• One MAHLE CS54580 lower gasket set for the 6.6L Duramax.
• Not included: the upper gasket set. MAHLE lists HS54580 for VIN code 1 (LB7) trucks and HS54580A for VIN code 2 (LLY) and 2006-2007 VIN code D (LBZ) trucks.
• Not included: cylinder head gaskets. MAHLE's upper sets exclude them too; you choose head gaskets by side (left or right) and by thickness grade.

About MAHLE

MAHLE began in 1920 as a small engine shop in Stuttgart, Germany, and made its name on pistons. Today it builds pistons, rings, liners, bearings, valves and gaskets for engine builders and the aftermarket. We stock hundreds of its Duramax, Cummins and Power Stroke part numbers; see the whole line on our MAHLE page.

Frequently asked questions

Does CS54580 include the head gaskets?

No. MAHLE lists 6.6L Duramax head gaskets separately, by side and by thickness grade: .95 mm (Grade A), 1.00 mm (Grade B) and 1.05 mm (Grade C). The grade is picked from measured piston protrusion, so measure before you order. We can help you match it.

What else goes into a full reseal?

MAHLE pairs this lower set with an upper gasket set and a left and right head gasket: HS54580 on a VIN code 1 LB7, HS54580A on a VIN code 2 LLY or a VIN code D LBZ. If the heads are coming off, ARP 230-4201 head studs fit 2001-2016 6.6L Duramax and are recommended whenever head gaskets are replaced, especially on trucks that tow heavy or are tuned.

Is CS54580B the same set?

No. In MAHLE's listing, CS54580B is the lower set for 2011-2016 6.6L Duramax trucks with VIN code 8 (LML) or L (LGH). CS54580 is the earlier set, listed here for 2001-2007 trucks. Match the part number to your engine before you buy.

Questions on fitment? Call the shop at the number in the header. We install everything we sell.