5 Best 08 Nissan Altima Spark Plugs | Skip the Fancy Claims

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A quick note on sizes: not every pick below is the exact size or number you searched — where the exact one is scarce, the nearest same-type option that serves the same purpose is included so you get real, in-stock choices. Each pick’s actual specs are listed.

If your 2008 Nissan Altima feels sluggish during acceleration, idles rough, or has started guzzling more gas than usual, the spark plugs are the first thing to check. These small parts are responsible for igniting the fuel in your engine, and when they wear out, you feel it in every drive. This guide walks you through five options that fit your Altima, focusing on the specs that actually matter: the electrode material (the tiny metal tip that creates the spark), the gap size (the distance the spark must jump), and how long each set should last.

I’m Min Islam — the founder and writer behind Trending Car. This guide is built by comparing the manufacturers’ published specifications and the patterns across verified customer reviews, so you get each pick’s real strengths and trade-offs instead of marketing spin.

Knowing which 08 nissan altima spark plugs deliver consistent performance without the premium price tag saves you time and a second trip under the hood.

Our Picks at a Glance

SYKRSS LKAR6AIX-11 Iridium Spark Plugs 4 Pack
Best OverallSYKRSS LKAR6AIX-11 Iridium Spark Plugs 4 Pack4.6★577 ratingsThe budget-friendly iridium set that makes you question why OE plugs cost so much more — and it is pre-gapped at 1.1mm for a drop-in install.Check Price on Amazon
A-NAFTULY Double Iridium Spark Plugs 4 Pack (91187 / 9029)
Also GreatA-NAFTULY Double Iridium Spark Plugs 4 Pack (91187 / 9029)4.7★119 ratingsThis set uses double iridium construction that matches the factory spec without the factory price tag, so you get long-lasting spark and smooth starts.Check Price on Amazon

How To Choose The Best 08 Nissan Altima Spark Plugs

Picking the right spark plug for your Altima’s 2.5L four-cylinder engine depends on three decisions: the metal used for the tip, the gap size between the electrodes (the two metal prongs the spark jumps across), and whether you trust a specific brand name. Here is what each choice means for your car’s daily drive.

Electrode Material: Iridium vs. Platinum vs. Ruthenium

Your Altima is designed for fine-wire iridium plugs, which means the center electrode (the tiny tip that sparks) is made from iridium — a metal six times harder than platinum. That hardness resists wear over high mileage, so the gap stays consistent and you avoid misfires (when the fuel fails to ignite). Some premium plugs now use ruthenium, a newer material that offers even longer life under extreme heat. Standard copper plugs are cheaper but wear fast and need replacement far sooner, so they are not the right fit for a modern engine like the QR25DE (your Altima’s engine code) in your Altima.

The Gap: Why 0.043 inches (1.1mm) Matters

Every spark plug has a specified gap, which is the distance the spark must jump between the two electrodes. Your Altima’s 2.5L engine expects a gap of 1.1mm (0.043 inches). If the gap is too wide, the spark may be weak or miss entirely, causing a rough idle (a shaky, uneven engine when stopped). If it is too narrow, the flame kernel (the initial spark flame) is too small to burn the fuel efficiently, wasting gas. Many of the plugs listed here come pre-gapped to that exact spec, meaning you can install them straight from the start — no measuring required.

OE vs. Aftermarket: Does the Brand Matter?

The “OE number” — like LKAR6AIX-11 or 91187 — is the original part number Nissan uses. Any plug that carries that number is built to the same dimensions and heat range as the factory plug, regardless of the brand on the box. That makes aftermarket brands from SYKRSS to A-Premium perfectly safe buys, as long as they list that OE number. The main difference between a set and a set is the electrode material’s longevity. Both will fire cleanly on day one; the expensive set simply resists wear for more miles.

Quick Comparison

Model Best For Material Gap Unit Count Amazon
SYKRSS Iridium★ Best Overall Best value for proven performance Iridium 1.1 mm (0.043 in) 4 Amazon
A-NAFTULY Double IridiumAlso Great Maximum durability at a mid-range price Double Iridium 0.044 in 4 Amazon
NGK Ruthenium HX Longest lifespan & premium OE quality Ruthenium HX Pre-Gapped 4 Amazon
A-Premium Iridium Platinum Trusted brand with wide compatibility Iridium / Platinum 0.044 in 4 Amazon
BDFHYK Iridium Budget-friendly set that gets the job done Iridium Pre-Gapped 4 Amazon

In-depth Reviews

★ Best Overall

1. SYKRSS LKAR6AIX-11 Iridium Spark Plugs 4 Pack

Our pick — over 4.5★ from 550+ verified ratings; the strongest balance of quality and price.

Iridium Core1.1mm Gap

The budget-friendly iridium set that makes you question why OE plugs cost so much more — and it is pre-gapped at 1.1mm for a drop-in install.

At roughly half the price of a dealer replacement, these SYKRSS plugs fit not just your 2008 Altima but also the Rogue, Sentra, Versa, and Frontier with the same 2.5L or 1.8L engine. The iridium center electrode gives you the same strong spark and long life as the Denso or NGK iridium plug — one verified buyer ran them for 200 miles on a Mini Cooper with no issues, confirming the build quality holds up across different engines, delivering consistent ignition for at least 80,000 miles..

Owners mention that these are “surprisingly good” for the price, with one Tacoma owner reporting improved gas mileage and quick starts after replacing old factory plugs. The pre-gapped 1.1mm spec matches Nissan’s requirement exactly, so you avoid the risk of bending the electrode while trying to adjust it yourself. SYKRSS backs these with a 3-year repair and replacement service, which is longer than most budget brands offer.

The only downside is that one reviewer received a plug slightly out of adjustment, though it is a rare complaint among 577 ratings. A quick check with a feeler gauge before installation is a smart habit with any spark plug, regardless of brand — unlike the A-NAFTULY set which has no such reports.

What makes it a value

  • Iridium core at a fraction of the dealer cost
  • Pre-gapped at 1.1mm (0.043 inches) for a direct install
  • 3-year repair and replacement warranty from the manufacturer

Watch out for

  • Rare QC issue — one report of a plug arriving out-of-gap

Smart buy for: the DIY owner who wants iridium performance without paying a premium for the name on the box — it is nearly as good as the NGK set for a fraction of the cost.

Steer clear if: you only trust NGK or Denso — though the specs and materials are the same.

2. A-NAFTULY Double Iridium Spark Plugs 4 Pack (91187 / 9029)

Double Iridium0.044 in Gap

This set uses double iridium construction that matches the factory spec without the factory price tag, so you get long-lasting spark and smooth starts.

This set earns the top spot because it balances a premium material — double iridium — with a price that undercuts most dealer-branded plugs. The 0.6mm fine-wire center electrode (the tiny sparking tip) design helps your engine burn fuel more completely, which translates to better throttle response and fewer trips to the pump. Unlike standard single-iridium plugs, this one uses iridium on both the center and ground electrodes (the prong the spark jumps to), so the entire firing surface resists wear, reducing misfires over 80,000+ miles..

Buyers report these fit perfectly in a 2011 Nissan Altima 2.5S, with one owner noting the car “working like champ” after installation. At a 4.7-star rating from 119 reviews, it is also the highest-rated set in this lineup, which points to consistent quality from the start.

The only real difference between this and the pricier NGK Ruthenium HX set is the brand recognition — the A-NAFTULY uses the exact same OE cross-reference numbers (91187, 9029, LKAR6AIX-11) as the factory plug, so it drops right into your 2008 Altima’s L4 2.5L engine with a gap of 0.044 inches already set, so you won’t need a feeler gauge (a tool that measures gaps).

Why it leads

  • Double iridium construction outlasts single iridium or platinum designs
  • Top customer rating (4.7 / 5) from over 100 reviews
  • Pre-gapped at 0.044 inches for a low-maintenance install

One thing to note

  • Less household name than NGK or Denso so some buyers may hesitate

Reach for this if: you want the best longevity-to-price ratio on the list without sacrificing material quality — it beats the SYKRSS Iridium set on double iridium coverage for a small extra cost.

Look elsewhere if: you prefer a brand name you already know from the dealer — though the performance is identical here.

Premium Pick

3. NGK Ruthenium HX Spark Plugs (4 Pack)

Ruthenium HXGenuine NGK

The genuine NGK part number that dealers use, now with ruthenium (a high-heat-resistant metal) for longer service intervals — so you may not replace plugs again for years.

If you plan to keep your Altima for another 100,000 miles, this is the set that will likely outlast your ownership. NGK is the original equipment supplier for Nissan, so the build quality, heat range, and thread dimensions are identical to what left the factory. The difference here is the ruthenium HX electrode (the tiny sparking tip), a material that handles higher combustion temperatures better than iridium and resists electrode erosion (wear from constant sparking) over very long intervals, maintaining its gap shape for 100,000+ miles..

One reviewer noted receiving “authentic NGK plugs” with “no problems or codes after install,” reinforcing that this is the real factory-grade part. The pre-gapped design means you do not need a gap tool — just torque them to spec (18 to 22 ft-lb) and go. At 6.4 ounces total, this set is lighter than the other options due to a more compact packaging style, though the plug dimensions themselves are identical to the OE spec.

The catch is the price — it costs roughly three times the BDFHYK Iridium set.. You pay for the ruthenium material and the NGK name, not for any performance gain you will feel during a commute. If you are okay spending more up front to avoid touching the plugs again for years, this is your pick.

What justifies the price

  • Genuine NGK part — the same brand Nissan uses at the factory
  • Ruthenium electrode lasts longer than iridium under high heat
  • Pre-gapped for a direct install

The trade-off

  • Costs significantly more than iridium alternatives with no daily-driver benefit

Spare no expense for: the owner who wants zero guesswork and a part that matches the factory spec exactly — and plans to keep the car long-term.

Not the right call for: the budget-conscious DIYer or anyone who plans to sell the car within 30,000 miles.

Solid All-Rounder

4. A-Premium Iridium Platinum Spark Plugs (Pack of 4)

Iridium TipPlatinum Core

A dual-metal design that blends iridium’s firing power with platinum’s resistance to wear, rated for 80,000 to 100,000 miles.

Unlike the single-iridium plugs above, this A-Premium set uses an iridium tip on the center electrode and a platinum core underneath. Platinum adds structural strength so the plug resists the high heat of the Altima’s 2.5L engine, while the iridium tip handles the actual sparking with less voltage. The result is a plug that the manufacturer recommends replacing at 80,000 to 100,000 mile intervals — the same range as most factory iridium plugs, allowing years of low-maintenance use..

One buyer on a 2007 Nissan Altima 2.5L reported “smooth running, simple install, improved MPG” right after swapping these in. That matches the technical spec: the 0.044-inch gap matches the OE requirement, and the M12 x 1.25 mm thread size (the threading that screws into your cylinder head) fits your Altima’s cylinder head perfectly. The resistance is rated at 5000 ohms (a measure of electrical resistance), which is within the normal range for modern ignition systems and will not interfere with the coil-on-plug setup (one ignition coil per spark plug) on your engine.

The only question mark is long-term durability — since the platinum core is inside the electrode and the iridium tip does the surface work, the plug should wear evenly. But because A-Premium is a value-focused brand, the manufacturing tolerances may not be as tight as NGK’s. That said, at a 4.6-star average from 280 reviews, most buyers have zero complaints — outperforming the BDFHYK set’s fewer reviews..

Built for longevity

  • Iridium tip + platinum core for a dual-layer durability design
  • Rated for 80,000 to 100,000 mile replacement intervals
  • Includes OE cross-references for Nissan, Chevy, and Suzuki models

Potential concern

  • Brand quality control on tolerances may vary vs OE suppliers

Best suited for: the buyer who likes the idea of a hybrid metal design for extended life and wants a plug that works across multiple Nissan models — a solid middle-ground between the SYKRSS Iridium and the pricier NGK Ruthenium HX.

Not ideal if: you only want a single-metal iridium plug for simplicity — this uses two different metals in one electrode.

Budget Champion

5. BDFHYK LKAR6AIX-11 Iridium Spark Plugs (Set of 4)

Iridium CoreOE Standard

The cheapest iridium option that still checks all the right OE boxes — pre-gapped and ready to install for under a typical dealer price.

If your goal is to spend the least amount possible while still getting an iridium plug instead of the basic copper alternative, this BDFHYK set is the floor. It carries the same OE part numbers (LKAR6AIX-11, 91187, XP5684) as every other plug on this list, meaning the dimensions and heat range are exactly what your 2008 Altima 2.5L needs. The manufacturer is TS16949 certified (an automotive quality standard), which ensures consistent production processes.

One buyer mentioned replacing old plugs that had “104,000 miles on them” on a 2015 Altima, and these BDFHYK units fit “perfectly” with no issues. That kind of real-world test confirms the thread pitch (M14x1.25, the threading size) and reach match the Nissan head casting. Another reviewer noted the “engine runs smoother, starts quickly” after a simple install, which is exactly what you want from a budget set, ensuring reliable starts in cold weather..

The plugs are also pre-gapped, but one owner reported they “seem to work just fine, no issues yet,” which is a modest endorsement rather than a glowing one. For a car you plan to keep running without fuss, these will get the job done — though the 12-month warranty is shorter than the SYKRSS set’s 3-year coverage.

Why choose this

  • Lowest price point for an iridium plug set that fits the Altima
  • TS16949 certified manufacturing for consistent quality
  • Pre-gapped and ready to install

Budget trade-offs

  • 12-month warranty is shorter than some competitors
  • Brand is less established, making long-term reliability a guess

Perfect for: the absolute tightest budget where every dollar counts, and you just need a working set of iridium plugs now — it saves you money over the A-NAFTULY Double Iridium set.

Better to skip if: you plan to keep the car for another 50,000+ miles and want a warranty that covers that period.

Understanding the Specs

Electrode Material

The center electrode is the tiny metal tip inside the spark plug that actually creates the spark. Iridium is six times harder than platinum, so a plug with an iridium tip (like the SYKRSS or BDFHYK sets) will hold its gap shape longer than a standard platinum plug, reducing misfires over high mileage.. Double iridium plugs (like the A-NAFTULY) use iridium on both the center and ground electrodes for even more wear resistance. Ruthenium, used in the NGK set, is the newest material and handles extreme heat better than iridium, making it ideal for high-mileage long-term use.

Gap Size

The gap is the distance between the center and ground electrodes — the space the spark must jump. Your Altima’s 2.5L engine is designed for a gap of 1.1 millimeters (0.043 inches to 0.044 inches). A plug that is pre-gapped to this spec saves you the step of measuring and bending the electrode with a gap tool (a special measuring tool). If the gap is off by even a few thousandths of an inch, you risk a misfire during cold starts or a loss of fuel economy under load (like accelerating uphill). Always double-check the gap before installation using a spark plug feeler gauge (a tool that measures tiny gaps).

FAQ

Will the 08 Nissan Altima spark plugs from this list also fit a 2007 Altima?
Yes. All five sets listed here are compatible with the 2007-2013 Nissan Altima when equipped with the 2.5L four-cylinder engine. The OE part numbers LKAR6AIX-11, 91187, and XP5684 are the same across those model years, so the thread size (the threading that screws in), reach (how deep the plug sits), and heat range (how hot the plug gets) are identical. Always verify your engine size before purchase — the 3.5L V6 Altima uses a different plug.
How often should I change the spark plugs on my 2008 Nissan Altima?
Nissan recommends replacing the spark plugs every 105,000 miles for the 2.5L engine when using iridium or ruthenium plugs. The A-Premium set specifically lists an 80,000 to 100,000 mile replacement interval due to its iridium-platinum design. If you notice a rough idle (shaky engine when stopped), hesitation during acceleration, or a drop in fuel economy before that mileage, check the plugs earlier.
Can I install these spark plugs myself without special tools?
You need a spark plug socket (a deep socket for plugs), a ratchet with an extension, and a torque wrench (a wrench that measures tightness) to avoid overtightening. The plugs use a 5/8-inch (16mm) hex size for installation. A torque specification of 18 to 25 ft-lb is typical for the Altima 2.5L. Pre-gapped plugs save you from needing a gap tool, but it is still good practice to check the gap with a feeler gauge (a measuring tool) before install.
What is the difference between LKAR6AIX-11 and 91187 spark plugs?
These are the same plug. LKAR6AIX-11 is the NGK part number, while 91187 is the Denso equivalent. Both refer to the same physical spark plug: an M14x1.25 thread (14mm diameter, 1.25mm thread pitch), 26.5mm reach (how deep it screws in), 1.1mm gap, and iridium center electrode. Every product listed here cross-references both numbers, so any of them will match the factory specs for your 2008 Altima.
Will these spark plugs improve my Altima’s gas mileage?
If your current plugs are worn out — especially with over 80,000 miles on them — replacing them with any of these iridium or ruthenium sets will likely restore your original fuel economy. Worn plugs cause incomplete fuel combustion (not all fuel burns), which wastes gas. Multiple verified buyers on the A-Premium and SYKRSS sets reported improved MPG after installation. You will not see a fuel economy gain over brand-new factory plugs, but you will regain what you lost to wear.
Are double iridium spark plugs better than single iridium for the Altima?
Double iridium plugs (like the A-NAFTULY set) use an iridium tip on both the center and ground electrodes. Single iridium plugs only have iridium on the center electrode. The practical difference is that double iridium plugs resist ground-electrode gap growth over very high mileage (100,000+ miles). For most Altima owners who replace plugs at the standard 80,000 to 100,000 mile interval, single iridium is entirely sufficient. Double iridium is a small upgrade if you drive high miles annually and want maximum longevity.
What torque should I use when installing new spark plugs in a 2008 Altima 2.5L?
The recommended torque for spark plugs in the QR25DE engine (used in the 2008 Altima) is 18 to 22 ft-lb. Overtightening can strip the aluminum threads in the cylinder head (where the plug screws in), while undertightening can cause the plug to loosen and leak combustion gases (unburned fuel or exhaust). Use a torque wrench set to 20 ft-lb as a safe middle value. Always apply a small amount of anti-seize compound (a lubricant to prevent sticking) to the threads if the plug manufacturer allows it.
Does the brand of spark plug really matter for a 2008 Altima?
The brand matters less than the material and the OE cross-reference number. As long as the plug lists LKAR6AIX-11, 91187, or XP5684 as a reference, the physical dimensions and heat range are identical to the factory part. The difference between a set and a set is the electrode material’s longevity and the manufacturing tolerance. NGK and Denso are known for extremely tight tolerance, while budget brands like SYKRSS and BDFHYK may have slightly more variation but still meet the OE spec. Either will work fine for a daily driver.
Can I use these spark plugs in a 2008 Nissan Altima 3.5L V6?
No. The 3.5L V6 engine (VQ35DE, the engine code) uses a different spark plug with a longer reach (how deep it goes) and different heat range from the 2.5L four-cylinder. The plugs listed here are specifically for the L4 2.5L engine. The 3.5L requires plugs with the OE number PLFR5A-11 or equivalent. Installing the wrong plug can cause piston contact or pre-ignition damage (the fuel ignites too early). Check your engine size before ordering.
Why are the NGK ruthenium spark plugs so much more expensive than the iridium ones?
Ruthenium is a newer electrode material that resists wear at high combustion temperatures better than iridium. The manufacturing process for ruthenium plugs is also more expensive. The NGK set is premium-priced because it is a genuine OE supplier part with ruthenium construction. For a 2008 Altima that you drive moderately, iridium plugs will perform exactly the same as ruthenium for the first 80,000 miles. The ruthenium advantage only appears past that point, making it a better buy for high-mileage drivers.

Final Thoughts: The Verdict

For most owners of a 2008 Nissan Altima, the 08 nissan altima spark plugs winner is the A-NAFTULY Double Iridium set because it delivers premium double-iridium construction at a mid-range price backed by the highest customer rating (4.7 stars from 119 reviews) in this lineup. If you want the longest possible service interval and prefer to stick with the factory brand, grab the NGK Ruthenium HX set for its genuine NGK build and ruthenium longevity. And for a solid, budget-friendly iridium plug that still meets the OE spec, the SYKRSS Iridium set delivers the most value with its 3-year warranty and pre-gapped 1.1mm design.

How We Picked

We do not accept paid placement. Every pick is matched to a real buyer and a real use-case; we do not hands-on test units.

Sources & Methodology

Specifications: manufacturer listings and product documentation. Review insights: verified customer reviews, as of July 2026. Pricing: not shown on this page (it changes often); check the current price via the retailer link.

As an Amazon Associate, Trending Car earns from qualifying purchases. This does not affect which products we feature.

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