When to replace spark plugs on a Lexus RX350?
Typically, plan spark plug replacement around 120,000 miles for RX 350 models with modern iridium or platinum plugs, but shorter intervals apply for severe driving or older copper plugs. Always verify the exact interval for your year and plug type in your owner’s manual or with a Lexus service advisor.
As Lexus continues to equip the RX 350 with long-life plugs, the replacement timeline blends official guidance with real-world wear. This article breaks down the standard interval, signs of wear, and what to expect when replacing spark plugs across common RX 350 generations.
What the manufacturer recommends
The RX 350 uses a 3.5-liter V6 in the 2GR family. Most models now ship with iridium or platinum spark plugs designed for long life. The official maintenance schedule typically calls for replacement at around 120,000 miles under normal driving. If your driving is considered severe—lots of short trips, extreme temperatures, towing, or dusty conditions—the interval may be shortened to roughly 60,000–90,000 miles. Always verify the exact interval for your specific VIN in the owner’s manual or with a Lexus service advisor.
Model-year variations
Here is a broad snapshot of what many RX 350 owners encounter across generations. Always confirm for your VIN, as plug type and interval can vary by year and market.
- 2007–2015 RX 350 (2GR-FE): Most units use long-life iridium/platinum plugs with a recommended replacement around 120,000 miles under normal driving; copper plugs (if installed as replacements) may require closer to 60,000 miles.
- 2016–2023+ RX 350 (2GR-FKS or later 2GR variants): Similar long-life plugs with a typical 120,000-mile interval under normal use; severe-service driving can shorten that window to about 60,000–90,000 miles.
In short, newer RX 350s generally follow a 120k-mile replacement rhythm with variations rooted in plug type and driving conditions.
When to replace: signs your RX 350 might be due
Even if you are far from 120,000 miles, certain symptoms can indicate worn spark plugs or related ignition issues. Watch for these warning signs that commonly lead to replacement decisions.
- Rough idle, engine misfires, or hesitation during acceleration
- Notable drop in fuel economy or reduced engine performance
- Check Engine Light with misfire codes (P030X) or misfire-related diagnostics
- Difficulty starting or extended cranking, especially in cold weather
- Visible fouling or damage during a routine inspection (when the coils are removed)
If you notice any of these symptoms, have a technician inspect the plugs, coils, and related ignition components to confirm whether replacement is necessary.
DIY vs professional replacement
Replacing spark plugs on a RX 350 is a manageable job for an experienced hobbyist, but many owners opt for a shop or dealership. The V6 layout requires careful coil removal, accessible spark plugs that sit deep in the cylinder head, and the right tools to avoid cross-threading or damaging ignition coils.
What to consider if you DIY
If you plan to replace spark plugs yourself, consider these practical guidelines and caveats before diving into the job.
- Always use the correct plug type and heat range specified for your engine and VIN; many RX 350 models use iridium/platinum plugs.
- Ensure you gap (if required) or verify that plugs are pre-gapped as specified, and avoid anti-seize compounds unless explicitly recommended by the plug manufacturer or Toyota/Lexus service data.
- Follow the torque specification and sequence for tightening to avoid damaging threads or cylinders; also inspect ignition coils and boots for wear.
- Keep track of replacement intervals and torque values; consider replacing all six plugs at the same time for balanced performance.
For many owners, a professional replacement provides the benefit of a diagnostic check, coil inspection, and warranty coverage on parts and workmanship.
What to expect during service
When replacing spark plugs on the RX 350, you can expect a multi-step service: disconnecting the negative battery (optional but common for safety), removing ignition coils, extracting old plugs, cleaning the bore, installing new plugs to the factory torque spec, inspecting coils and boot connectors, and a test run to ensure smooth operation. Dealers and shops will typically re-check for any fault codes after replacement and may perform a basic drive cycle to confirm there are no misfires.
Costs and timing considerations
Costs vary by shop, location, and plug type, but a typical spark plug replacement for a Lexus RX 350 in a professional shop ranges from a few hundred dollars to somewhat more, depending on parts and labor charges. If you opt for dealer service, be aware that labor rates and exact plug part numbers for your VIN can influence the price.
Plan around 60–90 minutes of labor in a typical shop, with longer times if diagnostic checks or additional maintenance is recommended. Always ask for a written estimate and the exact plug specification before work begins.
Summary
For most Lexus RX 350 models, spark plugs are designed for long life and are typically replaced around 120,000 miles under normal driving conditions. Severe driving conditions or older copper plugs can shorten that interval to roughly 60,000–90,000 miles. If you notice signs of wear, such as rough idle or reduced performance, have the plugs inspected and replaced as needed. Always verify the exact interval and plug type for your VIN in the owner’s manual or by consulting a Lexus service professional, and consider professional replacement to ensure proper torque and diagnostics.
How much does it cost to replace spark plugs in a Lexus RX350?
The average cost for a Lexus RX350 Spark Plug Replacement is between $493 and $668. Labor costs are estimated between $375 and $551 while parts are typically priced around $117.
Do I really need to change my spark plugs at 100,000 miles?
So, if good spark plugs are the key to avoiding these issues, how long do spark plugs last, exactly? The general rule of thumb about how often to change spark plugs is that they should be replaced after about 100,000 miles of driving.
Does a Lexus RX 350 have spark plugs?
Them. Now with a spark plug socket you can drop it down into the spark plug tubes. Break this free. And remove the spark. Plugs. Once it's unthreaded you can remove it there it is.
What year to stay away from Lexus RX 350?
Model Years You Might Want to Skip
While the RX 350 is generally a solid vehicle, a few model years have seen more complaints than others. It's wise to be cautious with the 2007, 2008, 2010, 2016, and 2017 models.
