Currently have the 2022 ES300h with the noise reduction wheels. Running on 235/45/18. Is 235/45/18 possible? Would that cause issues? What if i only put the larger sidewall wheels on the rears?

 

Try this site for info on potential interference, diameter difference, etc. If you are already running on 235/45/18, why are you asking if it's possible to use 235/45/18?

https://www.wheel-size.com/calc/?whe...cl=50mm&sr=0mm

 

Per title you mean 235/50R18 possible

235/45R18 diameter = 26.33 inches
235/50R18 diameter = 27.25 inches a 3.5% greater diameter which will effect various settings
Found this online AI response
Your decision research further

Using 235/50R18 on a 2022 Lexus ES300h with 235/45R18

For your 2022 Lexus ES300h, the OEM 18-inch setup is 235/45R18 on 18×8 ET45 wheels TireWheelGuide.com. The 235/50R18 is a slightly taller profile tire, but it’s still within the same width (235 mm) and wheel diameter (18") as the OEM.

Fitment compatibility:

• Width: Same (235 mm) — no interference with wheel fitment.
  
• Diameter: Same (18") — no change in ride height or clearance.
  
• Aspect ratio: 50 vs. 45 means the 235/50R18 is taller, which can give a slightly softer ride and marginally better grip, but may reduce high-speed stability compared to the OEM TireWheelGuide.com.
  
• Load/Speed ratings: You should match or exceed the OEM load index (94V) and speed rating (Y) for safety and warranty compliance TireWheelGuide.com+1.
  

Key considerations before swapping:

1. Check your wheel offset (ET45) — the 235/50R18 must fit the same ET45 18×8 wheels. If you’re using different rims, confirm offset and backspacing to avoid rubbing.
   
2. Ride height & clearance: The taller profile may slightly raise the ride height, but for most ES300h models, this is minimal and safe.
   
3. Load/Speed ratings: If your OEM tires are 98Y, you can use 94V or higher, but avoid dropping below 94V unless you increase tire pressure to compensate Lexus Owners Club.
   
4. Warranty & performance: Using a different size without Lexus approval may void certain warranty provisions.
   
5. Aesthetics & handling: The 235/50R18 will look similar but may feel slightly different in handling and ride comfort.
   

Bottom line:
Yes — 235/50R18 is a safe and common alternative to 235/45R18 on your 2022 ES300h, provided you use the same 18×8 ET45 wheels and maintain or exceed the OEM load/speed ratings. It’s a popular choice for a softer ride and slightly better grip, but you should confirm fitment with your wheels before installation.

 

235/50R18, 27.3"outer diameter, has been posted on this forum in the past.
Max I have seen reported is 27.7" (245/45R19 and 245/40R20)

Original is 94V at 35 psi.
300h cannot go past 115 mph, you absolutely don't need to go up to V (149 mph)
235/50R18 standard load index is 97, so your load capacity maintaining pressure would be between 31 and 32 psi.