Gwizzy

Hey guys. I originally ordered the NX350h but someone canceled an order for a RX350, so I jumped the gun and got that instead. I'm seeing a ton of debates regarding which fuel type to use. I understand that the 2023 rx350 now has a new turbo charged engine, so does that change the fuel required? I'm from Toronto and regular gas here is 87. I read on a dealers website that the 2022 rx350 can use a minimum of 87. Anyone know if that's the case for the 2023 rx350 as well? I'd rather not spend the extra money on more expensive fuel if I don't have to. Thanks in advance!

johnhey

based on User Manual:
2023 RX350 and RX500h "require" premium gas
2023 RX350h and upcoming Plugin Hybrid (probably 2024) "recommended" premium fuel BUT it is fine if you use regular fuel (87) , you may lose some performance (which 99% of people don't care)

so if you want to use regular fuel (87) right now your only option is RX350h.
2022 and 2023 RX have completely different engine

lexusnyca

Yes, premium. Costco at least is holding the line at 50 cents more per gallon for premium, I have seen other stations even higher. It's a negative to be sure for the turbo engine, depends on how many miles a year your drive. If you want the hybrid, the wait for it is going to be longer as the 350h is only 17% of Production (Lexus badly underestimated it I think).

Nasahos

Just discovered premium fuel,is required in the 2023 RX 350. I did not notice this in the RX booklet I got at the dealer. If one is not into performance, will it harm the engine to use regular fuel?

Eagleboy99

Could void your warranty. But the engine computer will adjust.

RolfK

(edited as I was mistaken about the rx 500h ):

For the 350h models premium is recommended but not required. Other models do need premium.

This info is in the owner manuals:

RX350h: Recommended to use premium unleaded gasoline with octane rating of 91 (Research Octane Number of 96) or higher for optimum engine performance. You may use unleaded gasoline with octane rating as low as 87 (Research Octane Number of 91). In this case, engine performance may be decreased. Use of octane rating unleaded gasoline with an octane rating lower than 87 may result in engine knocking. Persistent knocking can lead to engine damage.

RX500h: Select premium unleaded gasoline with an octane rating of 91 (Research Octane Number 96) or higher required for optimum engine performance and fuel economy. If the octane rating is less than 91, damage to the engine may occur and may void the vehicle warranty.

John89

What I don't understand is for pure gas model, it is same engine as Toyota Hybrid which 2023 doesn't require premium fuel.
Why does Lexus require if it is the same engine.

FMY421

Lexus "pure gas model" implies no hybrid component. So it can't be the same engine as a "Toyota Hybrid." I think you misspoke or misunderstood.

The newest generation NX and RX hybrids can use regular fuel. The newest generation NX 350 and RX 350 have a turbo 4 engine which requires premium fuel according to the manufacturer. The interesting question is why those require premium but the new Highlander turbo 4 does not. I don't know the answer, but I found a reddit thread. Maybe other readers here can comment on that.

Eagleboy99

We would have never placed an order if the 350h required premium fuel.

Nasahos

I am still confused whether or not the RX 350 requires premium gas. My vehicle is being built this week and so the only owners manual I have been reading is on line it states premium is required. As a senior citizen I am not into jack rabbit starts and most of my driving is local, so I wouldn’t be pushing the envelope.

ggebhardt

‘Take this as a hint. Your dealer will deliver your brand new RX with a tank full of 87 octane regular unleaded gas.

jer

Per the manual the RX350 non-hybrid states premium required. For the RX350h-hybrid, premium is recommended but not required.

Nasahos

My original post asks if I am not into performance, will it harm the engine to use regular gas? Several of the reply’s indicate that the computers will adjust the timing and it would be safe to use regular. Just want to do the right thing and not harm the engine. But it’s a waste of money to pay $1,00 more a gallon.

ggebhardt

‘You possibly could lose a couple of horsepower but regular unleaded will not harm your vehicle. The savings are well worth it.

Freds430

Used regular gas in last six vehicles that required premuim or recommended it and logged over a million miles. Noticed no difference in gas mileage or horsepower and of course zero engine problems. Want another opinion go to YouTube and search regular gasoline versus premuim and watch two clips one from Consumer Reports and one from CBC News.