---
product_id: 186808089
title: "Ford Racing (M-12405-35T) 10-17 Flex 3.5L EcoBoost Cold Spark Plug Set"
brand: "ford"
price: "$178"
currency: NZD
in_stock: true
reviews_count: 13
category: "Ford"
url: https://www.desertcart.nz/products/186808089-ford-racing-m-12405-35t-10-17-flex-3-5l
store_origin: NZ
region: New Zealand
---

# One heat range colder for peak performance Vehicle-specific fit for 3.5L EcoBoost engines Set of 6 precision gapped to .031 in. Ford Racing (M-12405-35T) 10-17 Flex 3.5L EcoBoost Cold Spark Plug Set

**Brand:** ford
**Price:** $178
**Availability:** ✅ In Stock

## Summary

> ⚡ Ignite your EcoBoost’s true potential with Ford Racing precision!

## Quick Answers

- **What is this?** Ford Racing (M-12405-35T) 10-17 Flex 3.5L EcoBoost Cold Spark Plug Set by ford
- **How much does it cost?** $178 with free shipping
- **Is it available?** Yes, in stock and ready to ship
- **Where can I buy it?** [www.desertcart.nz](https://www.desertcart.nz/products/186808089-ford-racing-m-12405-35t-10-17-flex-3-5l)

## Best For

- ford enthusiasts

## Why This Product

- Trusted ford brand quality
- Free international shipping included
- Worldwide delivery with tracking
- 15-day hassle-free returns

## Key Features

- • **Precision Gapped:** Factory-set .031 inch gap ensures consistent ignition and peak engine efficiency right out of the box.
- • **Tailored Fitment:** Designed exclusively for 2010-2017 Ford 3.5L EcoBoost engines—perfect compatibility guaranteed.
- • **Effortless Upgrade:** Quick 20-minute install transforms your ride’s throttle response and idle smoothness—no mechanic needed.
- • **Durable Copper Core:** High-quality copper core spark plugs deliver superior conductivity and long-lasting performance.
- • **Race-Ready Heat Range:** Optimized one step colder than stock for smoother, cleaner combustion and reduced misfires.

## Overview

The Ford Racing M-12405-35T Cold Spark Plug Set is a premium, vehicle-specific upgrade for 2010-2017 3.5L EcoBoost engines. Featuring a copper core and a heat range one step colder than stock, these plugs come pre-gapped at .031 inches and sold in sets of six. Designed to eliminate misfires and improve engine smoothness, they offer a quick, reliable tune-up that enhances performance and efficiency for the discerning Ford enthusiast.

## Description

One Heat Range Colder Than Stock. Sold In A Set Of 6. Gapped To .031 in..

Review: Absolutely outstanding !! - After tuning my 3.5 ecoboost and noticing a misfire on cylinders 1 and 5, I moved coils around. The misfire remained on same cylinders and I had good compression so the plugs were not performing well. I bought these due to colder heat range and closed the gap to .028" and the truck runs amazing. It runs smoother than it ever has !!
Review: 2020 Limited 3.5 HO - Use to replace my stock plugs at 40k after I got the 5 star tune. This helped stop the little stuttering at idle and the truck runs a lot smoother and cleaner. I got these per 5 stars recommendations as they are high performance. This was the easiest tune up I’ve never done, took me 20 minutes,10 minutes per side. Just make sure to get dielectric grease. I bought the boots but my truck came with a different kind of boot. Only problem is that if one of them breaks or is bad and you need to replace it you cannot buy them individually. Ford doesn’t even sell this part number anymore and you have to special order the spark plug if you need to replace one. The gap is closer is closer to .28 but if you’re tuned that’s ok. Honestly for the price and how fast you get them you can’t beat them, but I did have one go bad and I had to pay $13 to try to find one individually at that point you might as well just buy a new set.

## Features

- Innovative three-layer structure engineered to protect the interior of your vehicle with style, safety, and comfort in your daily ride
- Please reference the submodel information located on the far left within the Compatibility table under "Notes"
- Many products require vehicle-specific fitment
- View the Compatibility table to ensure the part fits your year, make, model and submodel

## Technical Specifications

| Specification | Value |
|---------------|-------|
| ASIN | B07HW1T57N |
| Automotive Fit Type | Vehicle Specific Fit |
| Best Sellers Rank | #40,292 in Automotive ( See Top 100 in Automotive ) #263 in Automotive Replacement Spark Plugs |
| Brand | Ford |
| Core Material | Copper |
| Customer Reviews | 4.6 4.6 out of 5 stars (322) |
| Date First Available | October 2, 2018 |
| Exterior | Painted |
| Is Discontinued By Manufacturer | No |
| Item Weight | 13.4 ounces |
| Item model number | M-12405-35T |
| Manufacturer | Ford Racing |
| Manufacturer Part Number | M-12405-35T |
| Model | Ford M-12405-35T |
| Product Dimensions | 10.75 x 4.5 x 4.5 inches |
| Thread Size | M14x1.25 |
| Top Material Type | Nickel |
| UPC | 756122008324 |
| Vehicle Service Type | Car |

## Product Details

- **Brand:** Ford
- **Core Material:** Copper
- **Thread Size:** M14x1.25
- **Top Material Type:** Nickel
- **Vehicle Service Type:** Car

## Images

![Ford Racing (M-12405-35T) 10-17 Flex 3.5L EcoBoost Cold Spark Plug Set - Image 1](https://m.media-amazon.com/images/I/41pA04xuw5L.jpg)

## Questions & Answers

**Q: Will this work on a 2015 ford taurus sho 3.5l ecoboost?**
A: Yes, I have them certainly installed in my 2015 Taurus SHO. They came gapped perfectly at .030 which is the latest  recommendation for the 3.5 ecoboost.

**Q: Are these already properly gapped ?**
A: F150 ecoboost are supposed to be at 28 so always double check

**Q: Will these fit my 2016 expedition with the 3.5 turbo eco boost? and will they come pre gapped?**
A: Yea they will fit and noticed they are pre gapped to .28-.30

**Q: Are these the original sp542 ? Or the new replacement?**
A: Yes these are the SP542 plugs. Ford discontinued the 542s and went with the performance version only now. The markings on the 542s and these plugs are exactly the same.

## Customer Reviews

### ⭐⭐⭐⭐⭐ Absolutely outstanding !!
*by C***S on August 29, 2025*

After tuning my 3.5 ecoboost and noticing a misfire on cylinders 1 and 5, I moved coils around. The misfire remained on same cylinders and I had good compression so the plugs were not performing well. I bought these due to colder heat range and closed the gap to .028" and the truck runs amazing. It runs smoother than it ever has !!

### ⭐⭐⭐⭐⭐ 2020 Limited 3.5 HO
*by T***S on May 4, 2024*

Use to replace my stock plugs at 40k after I got the 5 star tune. This helped stop the little stuttering at idle and the truck runs a lot smoother and cleaner. I got these per 5 stars recommendations as they are high performance. This was the easiest tune up I’ve never done, took me 20 minutes,10 minutes per side. Just make sure to get dielectric grease. I bought the boots but my truck came with a different kind of boot. Only problem is that if one of them breaks or is bad and you need to replace it you cannot buy them individually. Ford doesn’t even sell this part number anymore and you have to special order the spark plug if you need to replace one. The gap is closer is closer to .28 but if you’re tuned that’s ok. Honestly for the price and how fast you get them you can’t beat them, but I did have one go bad and I had to pay $13 to try to find one individually at that point you might as well just buy a new set.

### ⭐⭐⭐⭐⭐ 10 out of 10 quality
*by C***H on September 2, 2025*

Bought these because I was getting my raptor tuned and the cold plugs are recommended. Great choice

## Frequently Bought Together

- Ford Racing (M-12405-35T) 10-17 Flex 3.5L EcoBoost Cold Spark Plug Set
- Permatex 22058 Dielectric Tune-Up Grease, 3oz. - High Performance Dielectric Grease Used To Protect Terminals, Spark Plugs, Wiring And Other Electrical Connections Against Salt, Dirt, And Corrosion
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*Product available on Desertcart New Zealand*
*Store origin: NZ*
*Last updated: 2026-02-25*