How much to replace spark plugs on Lexus RX 350?

Replacing six spark plugs on a Lexus RX 350 typically costs about $250 to $600, depending on parts and labor and the shop you choose. A dealer might charge more, while an independent shop can be cheaper. The final price depends on plug type, access to the engine bays, and regional labor rates.

Cost snapshot

Here’s a practical breakdown of what drives the price and the most common ranges you’ll see in U.S. auto shops as of 2024–2025.

What affects the total price

Several variables influence the final bill: the type of spark plug installed (copper, platinum, or iridium); whether the dealership uses OEM parts or aftermarket equivalents; your local labor rate; and whether any related components like ignition coils show wear and need replacement.

Parts and labor breakdown

Cost components you should expect when replacing all six plugs are listed below. Prices are ballpark figures commonly seen in the U.S. market.

• Spark plugs (6 total): aftermarket iridium/platinum plugs typically $12–$25 each; OEM Denso/NGK plugs typically $20–$40 each. Total for 6: about $72–$150 for aftermarket; $120–$240 for OEM.


• Labor: time to perform the job is typically 1.5–2.5 hours on a RX 350 (rear bank access can affect this). Labor rates usually range from $100–$180 per hour in the U.S., depending on locale.


• Estimated total labor cost: roughly $150–$450, depending on time and rate.

Note that if ignition coils or other related components show wear and need replacement, or if a dealer quotes for OEM-only parts, the total can be higher. Always request a written quote that breaks out parts and labor.

DIY considerations

Replacing spark plugs yourself can save on labor, but it requires tools and some mechanical aptitude. The RX 350’s V6 layout means the rear bank plugs can be tricky to access, and you may need special extensions or a flexible shaft. If you’re not comfortable with the procedure, a professional is recommended to avoid damage to ignition coils or the engine sensors.

Maintenance context and plug-life expectations

Most RX 350 models use long-life ignition plugs. While some engines in this family run on iridium or platinum plugs rated for 100,000 miles, others may have shorter recommended intervals. Always check your owner's manual for the precise replacement interval and the recommended plug type for your exact year and engine code. If your vehicle has higher mileage and misfires or rough idle, a replacement may be warranted even if the plugs are within interval.

Summary

For a Lexus RX 350, replacing all six spark plugs typically costs between roughly $250 and $600 in the U.S., with the split between parts and labor depending on plug type and shop rates. OEM parts tend to push the price to the upper end, while aftermarket plugs and independent shops can offer savings. Always obtain a written quote that itemizes parts and labor and consider whether any related components will need replacement at the same time.

What year to stay away from Lexus RX350?

Years to avoid for the Lexus RX 350 include 2007, 2008, 2010, 2016, and 2017 due to common problems like oil leaks, engine issues, brake failures, and faulty sensors. The 2010-2012 models are particularly prone to a ruptured oil cooler line that can cause engine failure, while the 2007-2009 models had issues with cracking dashboards and a faulty brake master cylinder. The 2016 and 2017 models saw recalls related to airbags and issues with rain sensors, notes CoPilot.
 
You can watch this video to learn about the history of the Lexus RX 350 and common problems in different generations: 1mThe Miles DrivenYouTube · Dec 22, 2024
Years to avoid and why

• 2007–2009: These models are known for cracking dashboards and a faulty brake master cylinder that can lead to brake failure. 
• 2010–2012: A common and severe problem with these years is the oil cooler line, which can rupture and lead to engine failure. 
• 2016–2017: The 2016 model year had airbag recalls and was the first year of a new generation, which can lead to early bugs. The 2017 model had issues with the rain sensor and wipers, in addition to having its own airbag recalls. 

What to look for instead

• 2011–2015: These models generally have fewer issues, with the 2013–2015 models in particular being noted as more reliable. 
• 2018–2022: Models from these years are considered more reliable, especially those with the redesigned exterior. 
• 2020–2022: These are considered among the most reliable years, with the 2020 model year being a good choice. 

This video discusses the best Lexus RX 350 years to buy: 59sThe Miles DrivenYouTube · Dec 18, 2024

How much does it cost to replace spark plugs on a Lexus RX350?

The cost to replace the spark plugs in a Lexus RX 350 typically ranges from approximately $575 to over $1,600, depending on the model year and where the service is performed. While some sources estimate the cost between $575 and $800, higher estimates can reach $1,600 due to labor, especially since accessing the spark plugs can be challenging on these vehicles. 
Cost breakdown

• Average cost: Many estimate a price between $575 and $800 for the service. 
• Dealer/shop price: Prices at a dealer or shop can range from about $725 to over $1,630, with older models like the 2010 RX 350 often being on the higher end. 
• Part cost: The price for individual spark plugs is relatively low, around $10 each, but labor significantly increases the total cost. 
• Labor cost: The higher price is mainly due to the complex labor required to access the spark plugs, which involves removing several engine parts. 

Factors that affect cost

• Model year: Newer models may have slightly lower costs, while older ones can be more expensive. 
• Location: Prices vary depending on the shop or dealership and your geographic location. 
• Additional services: The total price can increase if other services are recommended at the same time. 

Do I really need to change my spark plugs at 100,000 miles?

Yes, replacing spark plugs at 100,000 miles is a common and often necessary maintenance task, as many modern vehicles have spark plugs rated to last that long. However, the exact interval depends on your vehicle's make, model, and the type of spark plug installed, so you should always check your owner's manual for the manufacturer's specific recommendation. 
This video explains when to change spark plugs and what happens if you don't: 1mHonest Mechanic ColoradoYouTube · Dec 24, 2023
Why it's important

• Engine performance: Spark plugs that are past their prime can cause rough idling, poor acceleration, and decreased fuel efficiency. 
• Preventing damage: Over time, worn-out plugs can put extra stress on other components, like ignition coils, and may seize in the engine block, making them harder to remove later. 
• Preventative maintenance: Replacing spark plugs is a form of preventative maintenance that can prevent more costly repairs down the line. 

This video explains why it's important to change spark plugs at 100k miles: 52sWhite One Auto, LLCYouTube · May 19, 2021
What to consider

• Owner's manual: Your vehicle's owner's manual is the most reliable source for the correct replacement interval and recommended plug type. 
• Spark plug type: The lifespan of spark plugs varies by material. Iridium plugs are often rated for 100,000 miles or more, while other types like copper or platinum have shorter lifespans. 
• Driving conditions: Severe driving conditions can shorten the life of spark plugs, so your interval may be shorter than recommended if you frequently tow, drive in extreme temperatures, or frequently start and stop. 

How often should spark plugs be changed on a Lexus RX350?

The Lexus RX 350 spark plug replacement interval is 60,000 miles for models with the 2GR-FKS engine (2016 and newer), which is also recommended for the emissions control warranty. Models with the older 2GR-FE engine have a recommended interval of 120,000 miles. Always refer to your specific owner's manual for the most accurate information for your vehicle. 
This video demonstrates the spark plug replacement process for a Lexus RX350: 56sProfessor's GarageYouTube · Mar 26, 2023

• 2016 and newer (2GR-FKS engine): Replace spark plugs every 60,000 miles. 
• Older models (2GR-FE engine): Replace spark plugs every 120,000 miles. 

This video shows the spark plug replacement for a 2017 Lexus RX350 with the 2GR-FKS engine: 57sProfessor's GarageYouTube · Jul 9, 2023
Signs of worn spark plugs
Misfiring or rough engine idle, Difficulty starting the engine, Reduced fuel efficiency, Difficulty accelerating, and Check engine light illuminates.