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TR5IX NGK Iridium Spark Plug | Genuine NGK Spark Plug

TR5IX NGK Iridium Spark Plug | Genuine NGK Spark Plug

Regular price $40.00 AUD
Regular price Sale price $40.00 AUD
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✓ Authorised Volvo Penta Dealer · Marine & auto specialists · Ships Australia-wide

🔧 Product Description

NGK Iridium Spark Plug – Part Number: TR5IX

Iridium NGK spark plugs offer a longer service life than a standard nickel-tipped spark plug: while nickel-alloy plugs offer a service life of roughly 20,000-40,000km, NGK Iridium IX spark plugs offer a service life of up to 60,000km, so fewer replacements are needed over time despite the higher initial cost.

Precious-metal spark plugs like the NGK Iridium IX also offer higher ignitability, achieved with an exposed fine-tip centre electrode that promotes superior flame growth compared with a standard spark plug. Iridium has a much higher melting point (2410°C) than nickel (1453°C), allowing the centre electrode diameter to be reduced from 2.5mm to 0.6mm – a smaller electrode mass that reduces the impedance to flame progress, helping acceleration, fuel consumption and idle quality.

⚙️ Key Features

  • Fine iridium-tipped centre electrode for a slow wear rate and stable idle
  • Longer service life than standard nickel plugs
  • Trivalent metal plating provides superior anti-corrosion and anti-seizing properties
  • Corrugated ribs reduce the risk of flashover
  • Pure alumina silicate ceramic insulator, providing superior strength and better heat transfer
  • Copper core aids in heat removal
  • Triple seals prevent leakage

📏 Specifications

  • NGK stock number: 7397
  • Thread: 14 mm
  • Reach: .708"
  • Hex: 16 mm (5/8 in)
  • Seat: Tapered
  • Terminal: Solid
  • Type: Projected

🚘 Application

Listed in NGK's application charts for marine, motorcycle, ATV and snowmobile equipment and automotive vehicles. The gap is not the same on all of them – the chart lists between 0.5 mm and 1.0 mm depending on the engine, so check the line for yours.

  • Crusader CLASSIC-5.7L PLUS EFI – Inboard Engine
  • Crusader CLASSIC-5.7L PLUS MPI – Inboard Engine
  • Crusader CLASSIC-7.4L MPI – Inboard Engine
  • Crusader PLATINUM-5.7L PLUS MPI – Inboard Engine
  • Crusader PLATINUM-7.4L MPI – Inboard Engine
  • Indmar 5.7L V8 EXCEPT LS1 (8 CYL GM SMALL BLOCK, 2005-1994) – Inboard Engine
  • Indmar 7.4L V8 (8 CYL GM BIG BLOCK, 2005-2003) – Inboard Engine
  • Indmar 8.2L V8 (8 CYL GM BIG BLOCK, 2005-2003) – Inboard Engine
  • Kodiak 5.7L V8 310 HP (350 CID, 2000-1999) – Inboard Engine
  • Marine Power GM V6 4.3L (262 CID, 2000-1998) – Inboard Engine
  • Marine Power V8 5.0L (305 CID, 2000) – Inboard Engine
  • Marine Power V8 5.7L (350 CID, 2000-1998) – Inboard Engine
  • Mercruiser 3.0L MPI ECT (4 CYL GM) – Inboard Engine
  • Mercruiser 4.3L TKS (6 CYL GM V-6) – Inboard Engine
  • Mercruiser 350 MAG MPI (8 CYL GM SMALL BLOCK, FROM 0L304700, 2006-2000) – Inboard Engine
  • Mercruiser 350 MAG MPI GEN+ HORIZON (8 CYL GM SMALL BLOCK, 0L304700 TO 0M309999) – Inboard Engine
  • Mercruiser BLACK SCORPION MX 6.2 (8 CYL GM SMALL BLOCK, 2006-2000) – Inboard Engine
  • Omc 2.3L COBRA (1990-1987) – Inboard Engine
  • Omc 3.0L COBRA (1998-1993) – Inboard Engine
  • Omc 3.0L COBRA HO (1998-1990) – Inboard Engine
  • Omc 5.0L COBRA EFI (1995-1993) – Inboard Engine
  • Omc 5.8L COBRA EFI (1996-1992) – Inboard Engine
  • Omc 5.8L KING COBRA EFI HO (1995-1993) – Inboard Engine
  • Volvo-Penta OCEAN SERIES - 4.3L OSI-XPD – Inboard Engine
  • Volvo-Penta OCEAN SERIES - 5.0L OSI-XPD – Inboard Engine

That is the 25 most common of 244 applications NGK's charts list for this plug – ask us to check yours.

🔄 Supersession & Cross Reference

NGK's cross-reference tables list this plug against these part numbers.

  • ACDelco: 12571533, 1835350T, 1835384T, 1835422T, 241-904, 241-906, 241-910, 25164640 and 8 more
  • Champion: 7408, 9204, 9204-2, 9204S, 9405, 9405-2, 9602, 9808 and 8 more
  • Bosch: 4011, 4205, 4211, 9602, 9657, H8DP, HR8D1133X, HR8DPX and 2 more
  • Autolite: XP103, XP103DP2, XP104, XP104DP2, XP105, XP105DP2, XP106, XP5243
  • DENSO: 4713, 5090, 5325, IT16, IT16TT, ZTJ16R10
  • Motorcraft: AGSF22PP, AGSF32W, AWSF22E
  • Beck Arnley: 1765290

📦 Condition

  • Brand new genuine product
  • Supplied in original packaging

Shipping & Delivery

Flat-rate shipping Australia-wide — $14.99 per order, no matter how many parts you add. Orders dispatch from our Kadina, South Australia store. Need it urgently or want to collect in person? Call us on 0412 532 984 before ordering.

Returns & Warranty

14-day change-of-mind returns — if it's not right or you ordered the wrong part, send it back within 14 days in new, unused condition for a refund or exchange. Manufacturer warranties apply to new parts. Full details in our Refunds & Returns policy.

Not sure this fits?

Ask us before you buy — we check part numbers and fitment every day. Call 0412 532 984 (Mon–Fri 8.30am–4.30pm) or message us through the contact page with your engine or vehicle details.

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