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If your Mercedes-Benz ML-Class exhaust manifold is failing, you may notice noise, reduced engine response, or an engine bay odor. Choosing the right replacement matters because the manifold affects exhaust flow, engine temperature management, and long-term reliability. This guide shortlists the top options for ML-Class applications and explains the evaluation criteria we used, so you can pick a unit that balances fitment and durability. Below you will find our top picks and the factors to weigh when deciding on a replacement.
Looking for other parts? See all Mercedes-Benz ML-Class parts & accessories.
Top Picks at a Glance
| Best Reviewed A top-rated pick with lots of positive feedback | A-Premium Exhaust Manifold Kit for Toyota 1.8L (with Gaskets and Hardware) |  |
| Best Quality Built to a higher standard if you want something more solid | Dorman 674-732 Exhaust Manifold Kit with Gaskets and Hardware |  |
| Best Budget The cheapest option that still gets the job done reliably | Marketplace Auto Parts Left Exhaust Manifold with Gaskets and Hardware |  |
| Most Sold A high-volume bestseller chosen again and again | Lamerto Replacement Exhaust Manifolds (pair) |  |
| Best Value for Money The sweet spot between price and what you get | Weonefit Exhaust Manifold with Catalytic Converter for Honda Civic 1.7L (2001–2005) |  |
| Best Overall The best all-around choice for most situations | Dorman 674-694 Passenger Side Exhaust Manifold Kit with Gaskets and Hardware |  |
1. A-Premium Exhaust Manifold Kit for Toyota 1.8L (with Gaskets and Hardware)
| Vehicle fitment | Toyota Corolla, Matrix, Scion xD 1.8L (specified years) |
|---|---|
| Material | Stainless Steel |
| Included components | Exhaust manifold, gasket, flange gasket, 2 bolts, 2 springs |
| Grade type | Standard Replacement |
This A-Premium kit supplies a direct-replacement exhaust manifold plus the primary gaskets, two bolts and two springs needed to reconnect the downpipe flange. It is intended for routine replacement when a cracked or leaking manifold causes exhaust noise, poor idle or failed emissions checks. The manifold is stainless steel and built to match factory mating surfaces, which helps simplify installation and reduces the need for machine work. Buyers will appreciate that the kit includes the doughnut-style gasket for the downpipe and a flange gasket so you have the parts often lost during removal. Some users report small fitment tweaks or a bracket modification may be required on specific vehicles, and one flange gasket in a few kits did not seat perfectly against the ports, so careful gasket alignment at install is important. The kit does not include a heat shield and uses standard replacement-grade construction rather than premium aftermarket performance tuning, so expect factory-like function rather than power gains.
Best for: Reliability-focused buyers who prioritize restoring factory-like operation and avoiding repeat trips to the shop will value this kit for routine manifold replacement and emissions repairs.
Less Ideal for: Those looking for a performance exhaust upgrade or a heat-shielded, heavy-duty racing manifold should consider purpose-built aftermarket options instead.
- Includes manifold plus necessary gaskets and basic flange hardware for a complete reinstall
- Stainless steel construction improves corrosion and heat resistance compared with cheaper cast options
- Manufactured to match factory mating surfaces for easier installation
- Direct-replacement design removes the need to source multiple parts separately
- Does not include a heat shield which may require reuse of the OEM shield
- One flange gasket in some kits has fitment variance and may need adjustment during installation
- Not intended as a performance upgrade, only a standard replacement part
Verdict A practical, reliability-oriented manifold kit that restores factory exhaust sealing and function but is not a performance upgrade.
2. Dorman 674-732 Exhaust Manifold Kit with Gaskets and Hardware
| Installation Type | Bolt-On |
|---|---|
| Automotive Fit Type | Vehicle Specific Fit |
| Manufacturer | Dorman Products |
| Position | Center |
| Bolt Pattern (Number of Holes) | 7 |
This Dorman exhaust manifold kit replaces a cracked or warped factory manifold with a ductile iron unit designed to resist heat-related warping and cracking. It comes as a complete bolt-on kit with the manifold, manifold gasket, two flange gaskets, three studs and three nuts to simplify a one-stop repair. The part is reverse-engineered from factory pieces so it typically fits without modification, and reviewers report solid fit and heavier feel compared with older factory castings. In practice this is used when the original manifold leaks, ticks, or has broken studs; it installs during an exhaust repair or routine replacement and speeds the job by supplying most hardware in the box. Limitations: the supplied gaskets and some flange nuts are reported as lower quality so you may want to source higher-grade gaskets and bolts for a long-term fix, and a few users needed minor grinding or extra bolts for clearance on specific engines. The kit prioritizes durability and fit over premium coatings or upgraded performance headers.
Best for: Performance-oriented owners who prioritize a durable, factory-quality replacement that restores exhaust sealing and reduces risk of future cracking during spirited driving and heavier use.
Less Ideal for: Drivers seeking an upgraded performance header or a coated high-flow manifold for horsepower gains should look at dedicated performance parts instead.
- Ductile iron construction reduces risk of warping and cracking compared with lower-grade cast manifolds.
- Complete kit includes manifold plus gaskets, studs and nuts to simplify a single-order repair.
- Reverse-engineered for direct, vehicle-specific bolt-on fit in compatible applications.
- Machined exterior and tested engineering aimed at meeting emissions and durability expectations.
- Widely used solution with many positive fitment reports across compatible vehicles.
- Included gaskets and some flange hardware are often lower grade and are commonly replaced by buyers.
- May require minor material trimming or additional fasteners for perfect clearance on certain engine layouts.
- Not a performance header — it focuses on durability and factory-style fit rather than increased flow or power.
Verdict A durable, factory-style replacement kit that restores sealing and durability for owners who want a high-quality repair rather than a performance upgrade.
3. Marketplace Auto Parts Left Exhaust Manifold with Gaskets and Hardware
| Position | Left |
|---|---|
| Compatible Engines | 6.2L V8 |
| Compatible Years | 2011-2019 |
| Package Contents | Manifold, 2 gaskets, 2 studs, 2 nuts |
This left driver-side exhaust manifold is a direct replacement intended to match the fit and function of a factory manifold and ships with two gaskets, studs, and nuts so you have the basic hardware needed for installation. It is typically used when a cracked or leaking manifold causes exhaust noise, rough warm-up behavior, or reduced fuel economy. The listing emphasizes durable construction to resist warping and cracking and several buyers report a good fit and improved performance after installation. The inclusion of downpipe hardware can help if original bolts are corroded, though a few buyers said gaskets were missing in some shipments so inspect the package before starting work. Installation on a restrictive engine bay can be time consuming and may require penetrating fluid, cutting seized bolts, or working from underneath the truck; expect a full day for removal and reinstall on a typical F-250. For a budget-focused replacement this part offers solid value, but verify all pieces are present before you begin the job.
Best for: Budget-conscious buyers who want a wallet-friendly factory-style replacement and are comfortable tackling a full-day DIY repair or arranging shop labor.
Less Ideal for: Shoppers who need a plug-and-play guaranteed complete kit with dealer-level inspection or those who prefer an upgraded performance manifold should look elsewhere.
- Sold with gaskets and basic mounting hardware so fewer separate purchases are needed
- Engineered to match factory fit and function for straightforward installation
- Durable construction intended to resist warping and cracking under heat
- Includes downpipe studs/nuts which can replace commonly seized hardware
- Some buyers reported missing gaskets in certain shipments
- Installation can be labor intensive in a tight engine bay and may require cutting seized bolts
Verdict A cost-effective factory-style left exhaust manifold that delivers solid fit and value for budget repairs provided you confirm all included gaskets and hardware before starting installation.
4. Lamerto Replacement Exhaust Manifolds (pair)
| Manufacturer Part Number | Lamerto 99746A17 MC-1-99746 |
|---|---|
| OEM Part Number | 51220, 9746, 99746, 99746A17, 99746A8, 5505, MC-1-99746, 51225, 9746-A, 99745, 9745, 18-1952-1 |
| Fitment Note | Replacement for Mer-Cruiser 4.3L V6, GM V6 229 and 262, Mer-Cruiser 175/185/205 |
These Lamerto replacement exhaust manifolds are sold as a left and right set intended to replace worn or damaged manifolds on compatible V6 engines. In use they mount where the cylinder head meets the exhaust system and route exhaust gases away from the engine; the listing includes the common OEM part numbers to help match fitment. The package arrives with the manifolds and, according to customer notes, the necessary bolts and washers for installation which simplifies a direct swap. For a risk-averse buyer this product offers a straightforward, like-for-like replacement path when a factory-quality manifold is no longer serviceable. Be aware this part is listed for Mer-Cruiser and GM V6 applications, so verifying flange pattern and bolt locations is essential before purchase. The manifolds are heavier-duty than universal styles, but professional installation is recommended because exhaust work requires correct torqueing and sealing to avoid leaks and exhaust heat issues. Expect a practical, budget-minded repair option if fitment is confirmed.
Best for: A risk-averse mainstream buyer seeking a direct, cost-conscious replacement who values parts that closely match factory behaviour and prefer to avoid custom or universal solutions.
Less Ideal for: Drivers who need guaranteed fitment or a part engineered specifically for Mercedes-Benz ML-Class engines should look for manifolds sold explicitly for that model or seek dealer-sourced factory replacements.
- Sold as a matched left and right set for a complete replacement
- Includes commonly referenced OEM part numbers to simplify fit verification
- Arrives with required hardware like bolts and washers per customer reports, easing installation
- Product listing specifies marine and GM V6 compatibility rather than Mercedes-Benz ML-Class fitment
- Installation requires correct sealing and torqueing so professional help may be needed to avoid leaks
- Manufacturer information and fitment guidance are limited so buyers must double-check compatibility before ordering
Verdict A practical matched replacement set for the listed GM and Mer-Cruiser V6 engines, but confirm fitment carefully if you need parts for a Mercedes-Benz ML-Class.
5. Weonefit Exhaust Manifold with Catalytic Converter for Honda Civic 1.7L (2001–2005)
| Fitment | Honda Civic 1.7L 2001-2005 |
|---|---|
| Manufacturer | Weonefit |
| OEM Part Numbers | 18160-PLM-A50, 18160-PLM-A00, 673-608 |
| Material | Stainless steel |
| Legal note | Not legal for sale in California |
This Weonefit assembly replaces the exhaust manifold and catalytic converter on 1.7L Honda Civic models from 2001–2005. It is intended for direct installation where the failed factory unit is removed and the replacement bolts up to existing flanges and oxygen sensor ports. Made from stainless steel, the part aims to resist heat and corrosion better than cheaper mild-steel options. In practice it serves drivers who need a complete manifold/converter swap rather than piecing together separate components, and it includes gaskets and spring bolts though some users report thin gaskets and reused hardware may be required. Several buyers report straightforward fitment and quieter operation after install, but multiple reviews show recurring check-engine lights or catalyst-efficiency codes on some vehicles, so emissions performance may be inconsistent. This unit is not legal for sale in California, and a small number of reviewers described sensor or bonding problems after installation. For a budget-conscious repair that restores exhaust flow, it can work well, but expect to verify oxygen sensor fit and be prepared to address emissions codes if they appear.
Best for: Practical optimizers looking for an affordable, one-piece replacement to get an older Civic running reliably again without overspending on dealer parts.
Less Ideal for: Buyers who need a guaranteed emissions-compliant solution or who prefer verified factory-quality converters should look for certified alternatives or dealer parts.
- Integrated manifold and catalytic converter simplifies a full replacement job.
- Stainless steel construction offers improved resistance to rust and heat compared with low-grade alternatives.
- Fits direct to the stock exhaust flanges and includes hardware and gaskets for installation.
- Multiple user reports confirm straightforward installation and restored exhaust function.
- Not CARB-compliant and cannot be sold for vehicles registered in California.
- Some buyers experienced persistent check-engine lights or catalyst-efficiency codes after installation.
- Included gaskets and springs may be thin or incomplete, requiring reuse of original hardware or aftermarket fasteners.
Verdict A cost-conscious, all-in-one manifold and catalytic converter replacement that can restore function on older Civics but may trigger emissions codes and is not CARB-compliant.
6. Dorman 674-694 Passenger Side Exhaust Manifold Kit with Gaskets and Hardware
| Installation Type | Bolt-On |
|---|---|
| Material Type | Stainless Steel |
| Compatible with Vehicle Type | Car, Truck |
This Dorman passenger-side exhaust manifold kit supplies a complete replacement intended to restore the exhaust path and seal on affected engines. It is sold as a bolt-on kit with the manifold plus two gaskets, studs, and nuts so you can complete a single-side repair without sourcing extra parts. The manufacturer says the casting is reverse-engineered from factory parts and made from ductile iron to resist the warping and cracking that can affect lower-grade castings, and users report it installs and seals well when properly fitted. Expect a demanding installation on some vehicles because removing broken studs and working in tight spaces is common; the included hardware is convenient but some installers prefer upgrading studs or gaskets before installation. Quality control appears generally good but occasional defects and damaged gaskets in transit have been reported, so inspect the kit on arrival. This kit is practical for owners who want a near-factory replacement and a one-box repair solution but be prepared for a time-consuming install and the possibility of replacing small hardware items for long-term durability.
Best for: A balanced all-round buyer who wants a cost-effective, near-factory replacement and values having all necessary parts in one kit to complete a passenger-side exhaust repair.
Less Ideal for: Buyers seeking a plug-and-play swap with minimal labor or those unwilling to deal with stud removal and potential minor hardware upgrades should consider professional installation or alternative options.
- Complete kit includes manifold plus gaskets, studs, and nuts for a single-order repair
- Ductile iron construction aimed at resisting warping and cracking compared with lower-grade castings
- Reverse-engineered for direct-fit installation to match factory mating surfaces
- Installation can be difficult due to broken studs and tight access, making it time-consuming for DIYers
- Some customers reported damaged gaskets or occasional casting defects on arrival
Verdict A one-box, factory-style passenger-side manifold replacement that saves time sourcing parts but may require patience and extra hardware during installation.
Choosing the Right Mercedes-Benz ML-Class Exhaust Manifold: Key Factors to Consider
Fitment and Bolt Pattern
Exact fitment matters because the manifold must align with the cylinder head flanges, studs, and exhaust ports. Incorrect bolt pattern or differing flange thickness can cause sealing failures, exhaust leaks, or interference with nearby components. When assessing fitment, confirm flange shape, stud spacing, and collector position to ensure a straightforward installation.
A manifold that matches factory mounting geometry minimizes the need for modification and reduces the risk of stress on bolts and gaskets. Proper fitment also helps preserve oxygen sensor and emissions component locations, which can be critical on ML-Class models.
Material and Thermal Resistance
Materials influence how a manifold handles heat cycles and whether it will warp or crack over time. Cast iron offers good heat tolerance and vibration damping, while certain stainless steels resist corrosion and can handle thermal expansion differently.
Choose a material that balances long-term thermal stability with corrosion protection for the driving conditions typical of the vehicle. A material that resists warping will maintain flange flatness and help prevent exhaust manifold leaks over the long term.
Sealing Surface and Gasket Quality
A flat, machined sealing surface improves the likelihood of a reliable seal between the manifold and the cylinder head. Poorly finished mating surfaces increase the chance of leaks and noise. The type and thickness of the gasket used also affect sealing under repeated heat cycles.
Look for manifolds that include or support high-quality gaskets designed for the ML-Class engine. Proper gasket choice and a well-prepared sealing surface reduce leak risk and make the installation more durable.
Collector Design and Exhaust Flow
Collector geometry and internal port alignment play a role in exhaust scavenging and backpressure. A poorly designed collector can create turbulence, increasing backpressure and reducing engine responsiveness. Conversely, a well-shaped collector helps smooth flow and supports consistent engine performance.
Evaluate how the ports merge and whether the collector aligns with the downstream exhaust piping to minimize turbulence and support predictable engine behavior.
Durability and Corrosion Protection
Exposure to heat, moisture, and road salt can lead to corrosion over time, especially in climates with winter road treatment. Corrosion can weaken mounting points or cause cracks at high-stress areas. Protective coatings, stainless materials, or robust casting practices extend component life.
Consider how the part will fare in your climate and driving conditions. Durable construction and corrosion-resistant finishes reduce the chance of premature failure and the need for repeat repairs.
Ease of Installation and Serviceability
Installation complexity affects labor time and the likelihood of errors during fitment. Manifolds that maintain stock geometry and provide clear access to studs, sensors, and heat shields simplify installation. Features such as welded-on studs or pre-drilled sensor ports can save time.
Also think about future servicing. Options that allow easier replacement of gaskets or sensors reduce labor on later repairs and make maintenance less costly and time-consuming.
FAQ
What are common signs of a failing exhaust manifold on an ML-Class?
Common signs often include a ticking or tapping noise on startup and during acceleration, a noticeable exhaust smell in the engine bay, and reduced throttle response. You might also see soot or discoloration around the manifold flange or experience increased engine noise under load.
Can I swap an exhaust manifold myself on an ML-Class?
Whether you can swap the manifold yourself depends on your mechanical experience and access to appropriate tools. Manifold removal often requires working in a tight engine bay, dealing with seized fasteners, and properly torquing bolts during reassembly. If you are comfortable with those tasks and follow proper procedures, it is achievable; otherwise professional help is advisable.
How do I diagnose an exhaust manifold leak?
Diagnosis often starts with a visual inspection for soot, cracks, or loose fasteners around the flange. Listening for distinct exhaust leaks during idle and acceleration can help localize the source. A smoke test or slight revving while listening with a stethoscope or a cardboard tube can confirm the leak location.
Should I reuse the old gasket when replacing the manifold?
It is usually best to replace the gasket whenever the manifold is removed. Gaskets compress and conform to surfaces over time, and reusing an old gasket increases the risk of leaks. A new gasket helps ensure a reliable seal after installation.
What causes an exhaust manifold crack on these vehicles?
Cracks commonly result from repeated thermal cycling, metal fatigue, or stress concentration at corners and mounting points. Corrosion and previous impact damage can also contribute. Proper material choice and secure mounting help reduce the likelihood of cracking.
Will replacing the exhaust manifold affect emissions components?
Replacement can affect sensor locations and the fit of downstream emissions hardware if the new unit does not match original geometry. Choosing a manifold that preserves sensor ports and alignment helps maintain proper sensor readings and reduces the chance of emissions-related issues.
How We Chose the Best Mercedes-Benz ML-Class Exhaust Manifold
We focused on parts that are explicitly listed for Mercedes-Benz ML-Class fitment and that address the common failure modes for these vehicles. Our primary filters included correct bolt-pattern and flange alignment, thermal performance and resistance to warping, material quality and corrosion protection, and the quality of mating surfaces and gaskets. We also considered build precision, such as consistent port dimensions and proper collector geometry, plus how well the part supports emissions components that may be present on ML-Class models. Units that required extensive modification to fit, or that lacked clear fitment documentation, were excluded. In short, we prioritized correct fit, thermal durability, sealing reliability, and construction quality when shortlisting options for this list.
Our full evaluation process is outlined in our review methodology.
Conclusion
When replacing an exhaust manifold on a Mercedes-Benz ML-Class, prioritize correct fitment and thermal durability. Ensure the flange alignment, bolt pattern, and sensor ports match the vehicle to avoid installation issues and leaks. Balance material choice and corrosion protection against ease of installation and long-term serviceability. Focus on the factors above to select a unit that minimizes future repairs and restores predictable engine performance.
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