A blown head gasket on a 6.7 Cummins is one of those repairs you only want to do once. Once the head is off and machined flat, the gasket you bolt back in determines whether your truck holds compression at 40 plus psi of boost or weeps coolant into cylinder seven again next winter. The 6.7 is a hard motor on gaskets because the deck moves under load, so layer count, fire ring design, and torque-to-yield bolt compatibility all matter more than the box price.
We looked at the gaskets that 6.7 owners and diesel shops actually run, from straight OEM Cummins replacements to thicker multi-layer steel units built for tuned, high horsepower trucks. Below are seven head gaskets ranked by real-world sealing reliability, fitment accuracy, build quality, and how well they survive abuse, so you can match the right gasket to whether your truck is stock, mildly tuned, or making serious power.
| Photo | Product | Score | Buy |
|---|---|---|---|
 |
Mahle Original 54580 Cylinder Head Gasket Best Overall Multi-layer steel, OE thickness, fits 2007.5 to 2018 6.7L Cummins |
9.5 | 🛒 Check Price |
 |
Cummins 4955230 OEM Head Gasket Best OEM Genuine Cummins multi-layer steel, direct factory replacement |
9.3 | 🛒 Check Price |
 |
Fel-Pro 26615 PT Head Gasket Best Value PermaTorque multi-layer steel, wide-application 6.7L coverage |
9.1 | 🛒 Check Price |
 |
Mahle 5475 Cylinder Head Gasket Set Best Complete Set Full head gasket set with MLS head gasket plus supporting seals |
8.9 | 🛒 Check Price |
|
ROADFAR Head Gasket Set for 6.7L Cummins Best Budget Set Complete head gasket set, multi-layer steel main gasket, 2007.5 to 2018 |
8.6 | 🛒 Check Price |
 |
Cometic C5950-040 MLS Head Gasket Best for High Boost Multi-layer steel, available in thicker bore sizes for built engines |
8.8 | 🛒 Check Price |
 |
Victor Reinz 61-10474-00 Head Gasket Best Premium OE Alternative Victor Reinz multi-layer steel, OE-engineered 6.7L sealing |
8.4 | 🛒 Check Price |
1. Mahle Original 54580 Cylinder Head Gasket: Best Overall
Mahle is one of the names that actually supplies original equipment gaskets to engine programs, and the 54580 is the gasket we reach for first on a clean, machined 6.7 deck. It is a true multi-layer steel design with bonded coating on the outer layers, which means it grabs sealant load quickly and holds it as the bolts stretch. On a stock or mildly tuned truck running sane boost, this is about as close to a no-drama repair as you get, and that reliability is why it sits at the top of the list.
The honest weakness is that this is a replacement gasket, not a performance upgrade. It is built to factory thickness with the stock fire ring profile, so if you are chasing 600 plus horsepower with aggressive timing and high drive pressure, you will eventually outrun what an OE-spec gasket can hold without studs and a fire-ringed head. For the vast majority of owners fixing a daily-driven or work truck, that limitation never comes into play, but big-power builders should look further down the list.
- Genuine OE supplier multi-layer steel construction
- Pre-coated sealing layers for fast clamp load
- Engineered to factory deck height and bore
Pros: Trusted OE manufacturer that supplies major engine builders; Excellent seal on stock and lightly tuned trucks; Consistent thickness keeps piston-to-valve clearance correct
Cons: Standard thickness only, no fire ring upgrade for big power; Fitment locked to specific year range, confirm yours first
2. Cummins 4955230 OEM Head Gasket: Best OEM
If you want the gasket Cummins itself specified for your engine, this is it. The 4955230 is the genuine factory multi-layer steel gasket, and the appeal is simple: there is no question about thickness, bore alignment, or coolant passage matching, because it is the same part the truck left the plant with. For owners restoring a stock 6.7 or anyone who wants to keep a build period-correct and predictable, the OEM route removes a whole category of doubt.
Choosing genuine over a quality aftermarket equivalent like the Mahle does cost you in availability rather than performance, since these are frequently slower to find and can require a dealer or specialty diesel supplier. It also offers no headroom for serious tuning, behaving exactly like the factory gasket it replaces, no better and no worse. That is precisely the point for a stock truck, but it means hard-tuned owners gain nothing here over the cheaper-to-find OE-grade aftermarket options.
- Genuine Cummins part number for guaranteed fitment
- Factory multi-layer steel sealing surface
- Matched to OE bolt torque and deck spec
Pros: Exact factory part, zero fitment guesswork; Backed by the engine maker itself; Ideal for warranty-sensitive and bone-stock trucks
Cons: No performance margin beyond factory power levels; Often harder to source than aftermarket units
3. Fel-Pro 26615 PT Head Gasket: Best Value
Fel-Pro is the brand most DIY and independent shop techs default to, and the PermaTorque MLS line is why. The 26615 uses a LaserWeld stopper layer that builds a controlled crush ring right around each cylinder, which helps it seal combustion pressure cleanly and, crucially, holds without the retorque ritual older gaskets demanded. For a one-and-done driveway or shop repair on a 6.7, that no-retorque behavior is a genuine convenience and a big part of why it earns its value badge.
Where it stays honest is power ceiling. This is a quality replacement gasket engineered to factory output, not a fire-ringed unit for a competition sled puller or a 700 horsepower street truck. It rewards a properly flat, clean deck, so the one install caveat worth repeating is to verify deck flatness before assembly. Skip that step and any MLS gasket can weep, but treat the surface right and the Fel-Pro will seal a stock-to-moderate 6.7 for the long haul.
- PermaTorque MLS technology for repeat sealing
- LaserWeld stopper layer around the bores
- Designed to seal without retorque on most installs
Pros: Strong reputation for trouble-free repeat seals; No-retorque design simplifies the job; Widely stocked and easy to source quickly
Cons: Standard performance, not a high-boost race gasket; Some batches benefit from a careful deck check before fitting
4. Mahle 5475 Cylinder Head Gasket Set: Best Complete Set
Pulling a 6.7 head means disturbing more than just the head gasket, and the Mahle 5475 set leans into that reality by bundling the main multi-layer steel gasket with the supporting upper-end seals you tend to replace at the same time. When you are already this deep into the job, having the matched components in one box keeps the install moving and spares you a mid-teardown run to the parts store for a seal you forgot. The core gasket carries the same OE-grade quality as Mahle’s standalone units.
The trade-off is that you pay for breadth you might not fully use. If your gaskets elsewhere are recent or you only need the head gasket itself, a full set includes pieces that end up in the spares drawer. It is also still a factory-thickness gasket, so it shares the same stock power ceiling as the single Mahle unit. For a thorough refresh-while-you-are-in-there job, though, the convenience is real and the quality is not in question.
- Includes head gasket and associated upper seals
- OE-grade multi-layer steel main gasket
- Reduces trips back to the parts counter mid-job
Pros: One box covers more of the teardown gaskets; Consistent OE-quality components throughout; Saves time hunting individual part numbers
Cons: Costs more upfront than a single gasket; May include seals you do not strictly need
5. ROADFAR Head Gasket Set for 6.7L Cummins: Best Budget Set
For a budget-conscious refresh, the ROADFAR set packs a multi-layer steel head gasket together with a wide assortment of supporting seals, which makes it appealing when you want broad coverage in one purchase. On a stock work truck that just needs to be put back together correctly, owners report it does the sealing job it is bought to do, and the sheer number of included pieces means fewer surprise stops during the teardown.
The realistic caution with value-tier aftermarket sets is consistency. It pays to lay out every gasket and dry-fit the critical pieces before you commit, because tolerances on lower-cost sets are not always as tight as the OE-supplier brands. It is also firmly a stock-replacement product, with no fire-ring upgrade for serious boost. Match it to a daily driver or a fleet truck on a tight maintenance plan and it makes sense; pair it with a built engine and you are asking more than it was designed to give.
- Comprehensive set with head gasket and seals
- Multi-layer steel main sealing gasket
- Broad year coverage for 6.7L trucks
Pros: Lots of included gaskets for the money spent; Convenient single-purchase teardown coverage; Easy to find and quick to ship
Cons: Aftermarket fitment can vary, check pieces before install; Not intended for high-horsepower tuned builds
6. Cometic C5950-040 MLS Head Gasket: Best for High Boost
Once a 6.7 makes real power, an OE-spec gasket is the wrong tool, and this is where Cometic earns its place. The C5950 series is performance multi-layer steel offered in a range of thicknesses and bore diameters, which lets a builder dial in clearance and clamp load for a high-boost combination. Run with quality head studs on a properly machined and ideally fire-ringed head, it is the kind of gasket that survives the drive pressure that pushes factory units past their limit.
That capability comes with conditions, and that is the honest catch. This gasket does not save a marginal install; it demands a flat deck, the right studs, and correct surface finish to seal, and it punishes shortcuts more than a forgiving OE gasket would. For a stock or lightly tuned truck it is unnecessary complexity, and a basic install can actually seal worse than a simple Fel-Pro if the supporting machine work is not there. Buy it because you are building, not because you are merely repairing.
- Performance MLS construction for high cylinder pressure
- Offered in multiple thickness and bore options
- Built to pair with head studs and a fire-ringed head
Pros: Holds up to aggressive boost and timing when set up right; Thickness options let you tune piston-to-head clearance; Respected name among diesel performance builders
Cons: Requires studs and proper machine work to perform; Overkill and finicky for a stock daily truck
7. Victor Reinz 61-10474-00 Head Gasket: Best Premium OE Alternative
Victor Reinz is the gasket aries of the same OE world Mahle lives in, and the 61-10474 is a clean, precision-stamped multi-layer steel option that belongs in the conversation whenever your first-choice brand is sold out. The layers are formed to spread clamp load evenly and the sealing beads around the coolant and oil passages are well executed, so on a flat, prepped 6.7 deck it gives you the predictable, leak-free result you expect from an OE-grade unit. It is a genuinely strong premium alternative rather than a compromise pick.
It lands a little lower here mostly on availability and the same factory-power ceiling that limits every OE-spec gasket on this list, not on quality. You also need to be careful matching the exact part number to your truck’s year and emissions configuration, since 6.7 applications changed over the production run. Get the fitment right and prep the surface, and there is little to separate it from the top OE choices; the ranking reflects how often owners can readily find and confirm it, not a flaw in the gasket itself.
- OE-supplier multi-layer steel design
- Precision-stamped layers for even clamp load
- Engineered sealing beads around fluid passages
Pros: Backed by a long-standing OE gasket maker; Clean, even sealing on a properly prepped deck; Solid alternative when other OE brands are out of stock
Cons: Fitment is year-specific, verify before ordering; Limited power headroom like other OE-spec units
Frequently Asked Questions
What are the symptoms of a blown head gasket on a 6.7 Cummins?
The classic signs are white sweet-smelling exhaust smoke, coolant disappearing with no visible external leak, bubbles in the coolant reservoir from combustion gases, milky oil on the dipstick, and overheating under load. On the 6.7 specifically, a creeping coolant level and pressure building in the cooling system after a hard pull are common early warnings. If you see oil and coolant mixing or compression pushing into the cooling system, stop driving and pull the head before you warp it, because continued running on a failing gasket often turns a gasket job into a head and gasket job.
Do I need head studs when I replace my 6.7 Cummins head gasket?
For a stock or lightly tuned truck, the factory torque-to-yield head bolts paired with a quality OE-spec gasket are designed to work and will seal fine. Head studs become important once you raise boost and cylinder pressure, because studs provide more even and higher clamp load than stretch bolts and let you retorque. If you are tuning, towing heavy at elevated boost, or chasing big power, install studs at the same time as the gasket. It is far cheaper to do it once with the head already off than to pull it again later.
Should I get a thicker head gasket for my tuned 6.7 Cummins?
Thicker performance gaskets exist mainly to fine-tune piston-to-head clearance and to add fire-ring robustness on built engines, not as a universal upgrade. For most street and tow trucks, a factory-thickness OE-grade gasket keeps piston-to-valve and compression where the engine was designed to run. Only step up to a thicker multi-layer steel unit like the Cometic when you are running studs, have done the supporting machine work, and have a specific clearance or sealing reason. Going thicker without a plan can drop compression and hurt low-end response with no benefit.
Does the head need to be machined before installing a new gasket?
Yes, almost always. Multi-layer steel gaskets are sensitive to surface finish and flatness, so the head and block deck should be checked for warpage and surface roughness before assembly. A 6.7 head that overheated is frequently warped, and even a slightly out-of-flat surface will cause an MLS gasket to weep no matter how good the gasket is. Have a machine shop check flatness and resurface to the correct finish if needed. Skipping this step is the single most common reason a freshly installed gasket leaks again.
Is OEM Cummins or aftermarket the better head gasket choice?
For a stock truck where guaranteed fitment matters most, a genuine Cummins gasket removes all doubt about thickness and passage matching. That said, top OE suppliers like Mahle, Fel-Pro, and Victor Reinz produce gaskets to the same engineering standard and are often easier to find, so a quality aftermarket MLS unit is a smart choice for most owners. The real divide is not OEM versus aftermarket but OE-grade versus bargain. Stick with reputable multi-layer steel from a known supplier, and for big power move to a dedicated performance gasket plus studs.
Our Verdict
For most 6.7 Cummins owners, the Mahle Original 54580 is our top pick because it delivers genuine OE-supplier multi-layer steel quality, drama-free sealing on stock and lightly tuned trucks, and the kind of fitment confidence that makes this big job a one-time repair. Our runner up is the Cummins 4955230 OEM gasket, the obvious call when you want the exact factory part and zero fitment guesswork. If your truck is built and making serious boost, skip both and step up to the Cometic C5950 with head studs and proper machine work, and remember that on any of these, a flat, properly resurfaced deck matters as much as the gasket you choose.
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