Infiniti FX35 Engine Valve Cover Gasket and Oil Leak Guide (2003-2012)
Burning oil smell or seeing leaks? Your FX35's valve cover gaskets are a likely cause, but the fix might be more than just a gasket.
- The most common leak is from the spark plug tube seals, which requires replacing the entire valve cover, not just the gasket.
- Before ordering, pull an ignition coil to check for oil in the spark plug well. This determines if you need just gaskets or new covers.
- The engine changed in 2009 (VQ35DE to VQ35HR); ensure you buy parts for your specific model year as they are not interchangeable.
- For best results, choose OEM, Beck Arnley (often repackaged OEM), Victor Reinz, or Mahle gaskets to avoid premature failure.
Is Your FX35 Leaking Oil? Here's What to Know
If you're smelling burning oil or seeing drips under your 2003-2012 Infiniti FX35, the valve cover gaskets are a common suspect. Over time, the rubber gaskets get hard and brittle from constant heat cycles, causing them to shrink and crack. This allows oil to seep out, typically onto the hot exhaust manifolds, which creates that distinct burning smell.
The Real Problem: Spark Plug Tube Seals
On the VQ35DE (2003-2008) and VQ35HR (2009-2012) engines, the most common and frustrating leak comes from the spark plug tube seals. These are the round seals that are part of the valve cover gasket set. Unfortunately, on the original plastic OEM valve covers, these tube seals are permanently integrated and cannot be replaced separately. If you find oil in your spark plug wells—a common cause of engine misfires— 🎬 See what happens when oil leaks into the spark plugs.you cannot just replace the gaskets. You must replace the entire valve cover assembly. Many owners learn this the hard way after a gasket-only replacement fails to fix the leak.
Generation Differences: VQ35DE vs. VQ35HR
It is critical to buy parts for the correct year range, as the engines are different.
- 2003-2008 Infiniti FX35: Uses the VQ35DE engine. 🎬 Watch this step-by-step gasket replacement on a 2008 FX35.
- 2009-2012 Infiniti FX35: Uses the updated VQ35HR engine. 🎬 See a detailed walkthrough for the 2009-2012 VQ35HR engine.
The valve covers and gaskets for these two engines are not interchangeable. Always confirm your vehicle's year before ordering.
Choosing the Right Aftermarket Gasket Set
When shopping for a replacement, quality matters. A cheap, poorly fitting gasket will have you doing this labor-intensive job all over again. Based on owner experiences and brand reputation, here is a breakdown of available brands.
Tier 1: OEM or Better
Beck Arnley: This is often the top recommendation in aftermarket parts for a reason. Forum users report that Beck Arnley valve cover gaskets for the FX35 are frequently repackaged OEM Nissan parts. If you want OEM quality without the dealer price tag, this is your best bet.
Tier 2: High-Quality Aftermarket
Victor Reinz (Reinz) & Mahle: Both are German brands with a strong reputation for being original equipment suppliers to many European carmakers. They are known for high-quality materials and precise fitment. Many mechanics consider them a reliable choice if OEM or Beck Arnley are not available.
Tier 3: Economy/Mixed Reviews
Fel-Pro: While Fel-Pro is a huge name in gaskets, owner feedback for this specific FX35 application is mixed. Some users have reported issues with fitment, particularly receiving a kit where one gasket did not fit correctly, leading to continued leaks. While they are a budget-friendly option, it comes with some risk on this particular engine.
Apex: This is generally an economy-focused brand. Less information is available on its specific performance for the FX35, so it should be considered a budget option with potential quality variance.
Pro Tip: Consider New Valve Covers
Since the main failure point is often the non-replaceable spark plug seals, inspect your spark plug wells before ordering. If there is oil, save yourself the headache and purchase complete new valve cover assemblies, not just the gaskets. Aftermarket valve covers often come with new gaskets pre-installed.
| Part | Cost Estimate |
|---|---|
| Aftermarket Gasket Set | $14 - $68 |
| OEM Gasket Set | $40 - $70 |
| Aftermarket Valve Cover Set (with gaskets) | $80 - $200+ |
| OEM Valve Cover Set (with gaskets) | $400 - $500+ |
| Shop Labor | $274 - $402 |
Frequently Asked Questions (FAQ)
Why is there oil in my spark plug wells?
Oil in the spark plug wells is caused by failed spark plug tube seals. On the FX35's original valve covers, these seals are part of the cover and cannot be replaced on their own. This means you must replace the entire valve cover to fix the leak.
Can I just replace the gaskets and not the whole valve cover?
You can only do this if your leak is exclusively from the outer edge of the valve cover and your spark plug tube seals are still in perfect condition. Given the age of these vehicles, it is highly likely the tube seals are also failing. It is best practice to at least inspect them before deciding. If you see any oil in the spark plug tubes, you need new valve covers.
Is OEM better than aftermarket for this part?
For the FX35, using a high-quality part is crucial. While OEM is always a safe choice, some aftermarket brands offer comparable or identical quality. Beck Arnley is widely reported to be repackaged OEM for this application, making it an excellent choice. Low-cost, economy brands have a higher risk of premature failure or poor fitment.
Are there any recalls for the valve cover gaskets?
No. There are no active recalls or Technical Service Bulletins (TSBs) from Infiniti or the NHTSA specifically for leaking valve cover gaskets on the 2003-2012 FX35.
How difficult is this job to do myself?
This job is considered moderately difficult and requires 3-5 hours for an experienced DIYer. It involves removing the engine cover, air intake piping, and both the upper and lower intake manifolds to access the valve covers. It requires careful organization of bolts and disconnection of several sensors and hoses. It is doable at home, but it is not a beginner-level repair.
Helpful Videos
Technical Specifications
OEM Part Numbers: 13264-AM600 13264-AM610 13264-JK20A 13264-JK20B 13270-8J102 13270-8J112
The primary distinction is between parts for the 2003-2008 VQ35DE engine and the 2009-2012 VQ35HR engine. Gaskets and valve covers are not cross-compatible between these two engine types. The original valve covers are made of plastic with integrated, non-serviceable spark plug tube seals.
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The information in this article is provided for general reference and educational purposes only. Vehicle specifications, procedures, and part compatibility can vary by production date, trim level, and region. Always consult your vehicle's factory service manual and verify part numbers before purchasing or performing repairs. Safety-critical components such as airbags, seat belts, and braking systems should be installed by a qualified professional.
- INFINITI FX35:
- 🎬 Helpful Videos
- 🛍️ Shop This Part
- Is Your FX35 Leaking Oil? Here's What to Know
- The Real Problem: Spark Plug Tube Seals
- Generation Differences: VQ35DE vs. VQ35HR
- Choosing the Right Aftermarket Gasket Set
- Tier 1: OEM or Better
- Tier 2: High-Quality Aftermarket
- Tier 3: Economy/Mixed Reviews
- Pro Tip: Consider New Valve Covers
- Frequently Asked Questions (FAQ)
- 🎟️ Get 5% Off