Does the 2019 Lexus RX 350 require premium gas?

The 2019 Lexus RX 350 does not require premium fuel. Regular unleaded gasoline with an octane rating of 87 or higher is typically sufficient. Premium fuel is optional and not required for normal operation.

To understand why, it’s helpful to look at the vehicle’s fuel guidance as published by Lexus. The owner’s manual for the 2019 RX 350 states that regular unleaded gasoline with an octane rating of 87 or higher is acceptable. The engine management system is designed to adapt to the octane level, and there is no mandatory premium requirement for everyday driving. The RX 350 is also compatible with ethanol-blended fuels up to 10% (E10) in most markets. While higher-octane fuels can be used, they typically do not produce a meaningful performance gain for routine driving, though some drivers may notice marginal differences under certain conditions.

Fuel octane requirements

Key facts about octane and the RX 350’s fuel guidance are summarized below.

• The RX 350 accepts regular unleaded gasoline with an octane rating of 87 or higher.


• Premium fuels (often 91–93 octane) are not required for normal operation, but can be used if you choose.


• In most markets, the vehicle is compatible with E10 gasoline (up to 10% ethanol).


• Fuels with ethanol content higher than what the manual allows should be avoided; check local fuel standards if you’re unsure.

Bottom line: For daily driving, regular 87-octane fuel is the practical choice; premium is optional and mainly a personal preference or a consideration in specific situations.

Performance, economy and maintenance considerations

Understanding how octane affects the RX 350’s performance and efficiency can help you decide what to buy at the pump.

• Regular 87-octane fuel is generally sufficient for normal driving in the RX 350.


• Premium (91–93 octane) may offer marginal benefits under high-load conditions, such as steep climbs or towing, but gains are not guaranteed for typical daily use.


• Fuel economy differences between regular and premium on this engine are usually small for everyday driving.


• Using premium does not harm the engine; it simply costs more per gallon with limited or no noticeable performance improvement in standard use.

Conclusion: For most owners, sticking with regular fuel is the sensible and cost-effective choice. Reserve premium for specific driving scenarios or personal preference.

What this means for RX 350 owners

Practical takeaway: You can confidently fill up with regular 87-octane gasoline at most fuel stations. If you notice knocking or pinging under heavy acceleration or extreme heat, you might experiment with a higher-octane fuel, but consult the owner’s manual or a Lexus service advisor first to confirm whether you’re experiencing a true need for premium fuel.

Summary

The 2019 Lexus RX 350 does not require premium gas. Regular unleaded gasoline with an octane rating of 87 or higher is acceptable, and the vehicle is compatible with E10 fuels. Premium fuel is optional and may offer only limited benefits for ordinary driving. Always consider local fuel options and follow the guidance in the owner’s manual for the best balance of performance and cost.

What Lexus does not need premium gas?

Several Lexus models do not require premium gas, including the Lexus ES 350, RX 350 (older models), NX 250 (some model years), and hybrid models like the UX 250h and NX 350h/450h+ (where premium is recommended but not required). To confirm the correct fuel for a specific vehicle, always check the owner's manual or the vehicle's fuel-door label. 
Models that typically use regular unleaded (87 octane) 

• Lexus CT 200h
• Lexus ES 300h and ES 350
• Lexus HS 250h
• Lexus NX 250 (some model years)
• Lexus NX 300h (older models)
• Lexus RX 350 (models from approximately 2012-2022)
• Lexus UX 250h (some model years) 

Models where premium is recommended but not required 

• Some hybrid models, such as the NX 350h and NX 450h+, can use regular gas, but using premium is recommended for optimal performance and to prevent potential engine knocking. 

How to be certain

• Check the owner's manual: This is the most reliable source of information for your specific vehicle. 
• Look at the fuel door: The required fuel type is often listed inside the fuel-filler door. 

What happens if you accidentally put 87 instead of 91 in a Lexus?

If you accidentally put 87 octane instead of 91 in a Lexus, your car will likely experience a loss of power and performance, and you may hear engine knocking or pinging. Modern Lexus models have knock sensors that adjust the engine's timing to prevent damage from lower octane fuel, but this reduces power. While a single tank is unlikely to cause serious damage, it's best to avoid heavy acceleration and fill up with the correct 91+ octane fuel as soon as possible to dilute the lower-octane gas. 
What to expect

• Reduced performance: The engine may feel sluggish, with slower acceleration and reduced power output. 
• Engine knocking or pinging: This is a rattling or pinging sound that occurs when the fuel detonates prematurely, especially under acceleration or when going uphill. 
• Lower fuel efficiency: You may visit the gas station more frequently, which could negate any short-term savings on fuel. 
• Potential for damage (older vehicles): Older Lexus models may not have the same sophisticated knock sensors. Repeatedly using 87 octane in a car that requires 91 can lead to engine damage over time. 

What to do

1. Avoid heavy acceleration: Drive gently to prevent the engine from knocking. 
2. Fill up with premium fuel: When your tank is low, fill it with the correct 91+ octane gas. This will dilute the remaining 87 octane fuel. 
3. Monitor your engine: Pay attention to any persistent knocking or changes in performance. 
4. Consult your owner's manual: Check the manual for the specific octane requirement of your Lexus model. 
5. Seek professional help if needed: If the knocking continues after filling up with premium gas, have a mechanic check the knock sensors and ignition timing. 

What year to stay away from Lexus RX 350?

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

Can I use regular gas in my Lexus RX 350?

Whether you can use regular gas in a Lexus RX 350 depends on its model year; models from 2012–2022 can use regular (87 octane) unleaded, while newer models from 2023 and beyond typically require premium (91 octane) unleaded gas. It is crucial to check your owner's manual for the correct fuel requirement to avoid potential engine issues like reduced performance, increased emissions, or damage. 
2023 and newer RX 350 models

• Most newer models with a turbocharged engine require a minimum of 91 octane premium unleaded gas.
• Using regular gas in these models is not recommended and can lead to decreased engine performance and mileage. 

2012–2022 RX 350 models

• These models are designed to run on regular unleaded gasoline (87 octane). 
• While you can use premium gas, it is not required and will not provide significant performance benefits. 

Important considerations

• Always check your owner's manual: This is the most reliable source for your specific vehicle's fuel requirements. 
• Avoid high-ethanol fuel: Do not use gasoline with more than 15% ethanol, and avoid fuels containing methanol or MMT. 
• Consider the long-term cost: For newer models requiring premium gas, the cost of using the correct fuel is a long-term investment to ensure proper performance and longevity of the engine.