What kind of power steering fluid does a Lexus RX 350 take?
Power steering in the Lexus RX 350 uses automatic transmission fluid (ATF), not a dedicated power-steering fluid. The exact specification varies by model year and market, but Toyota/Lexus ATF WS is standard for most newer RX 350s; older models may call for Dexron II/III-compatible ATF. Always verify with your owner’s manual or dealer.
Overview by generation
The RX 350 has evolved, so there is no single fluid spec across all years. The following guidelines cover common cases.
Newer RX 350 models (2010s–present)
For most RX 350 models produced from around 2010 onward, Toyota/Lexus official guidance specifies the use of Toyota ATF WS (World Standard) for the power steering system.
- Toyota ATF WS (World Standard) – Official recommendation for many modern RX 350s.
- Do not use engine oil, hydraulic fluid, or any power steering fluid not specified by the manual.
In practice, this means when servicing the power steering, choose ATF WS that meets Toyota's specification and avoid mixing with other fluids.
Older RX 350 models (2007–2009)
Earlier generations typically called for a Dexron II/III-compatible automatic transmission fluid for the power steering circuit, though some markets may differ.
- Dexron II/III ATF – Common guidance for power steering in older RX 350s.
- Or Toyota ATF that meets Dexron II/III compatibility, if specified in your manual.
Always verify against your owner's manual or a Lexus dealer, since regional variations exist and the reservoir cap may indicate the exact specification.
How to verify the correct fluid in your RX 350
To ensure you use the correct type, check these sources before adding or replacing fluid:
- Owner’s manual for fluid specification (ATF WS, Dexron II/III, etc.).
- Power steering reservoir cap markings, which often indicate the required ATF type.
- Consult a Lexus dealer or certified mechanic if the manual is unavailable.
Using the wrong fluid can cause steering noise, poor performance, or damage to the power steering pump, so confirmation is essential.
Summary
- The RX 350’s power steering uses ATF, not a separate steering fluid.
- Modern RX 350s typically require Toyota ATF WS (World Standard).
- Older models (2007–2009) commonly use Dexron II/III-compatible ATF.
- Always verify with the owner's manual or dealer before servicing.
Bottom line: Use the ATF specified for your exact model year and market, and when in doubt, consult a Lexus service professional to protect your steering system.
