Going to be moving to the RXL for the extra space (although it's not much, it's just enough for our needs). Issue I'm having is The RXL Luxury is only $800 less than the RXhL Luxury, which I find somewhat amazing. The RXL MSRP is $64,095 and the RXhL is $64,895 - both are 2018's. Both have identical options in the Luxury package, both have captains chairs, but the hybrid has heated rear captains. I've never owned a hybrid before, but I drove the 450h and really liked the CVT as it didn't have the jerkiness of the 8 speed in my current RX. Gas would be a wash as the hybrid takes premium and the difference is almost .60 a gallon where I live. I've gotten the discount's down to 7% off ( which is better than I thought as local dealer is a plus dealer and originally would budge off of invoice) and opted not to take the 2k lexus cash in lieu of 0% financing. Any thoughts appreciated.....

 

Going to be moving to the RXL for the extra space (although it's not much, it's just enough for our needs). Issue I'm having is The RXL Luxury is only $800 less than the RXhL Luxury, which I find somewhat amazing. The RXL MSRP is $64,095 and the RXhL is $64,895 - both are 2018's. Both have identical options in the Luxury package, both have captains chairs, but the hybrid has heated rear captains. I've never owned a hybrid before, but I drove the 450h and really liked the CVT as it didn't have the jerkiness of the 8 speed in my current RX. Gas would be a wash as the hybrid takes premium and the difference is almost .60 a gallon where I live. I've gotten the discount's down to 7% off ( which is better than I thought as local dealer is a plus dealer and originally wouldn't budge off of invoice) and opted not to take the 2k lexus cash in lieu of 0% financing. Any thoughts appreciated.....

 

I switched to the hybrid, and have never regretted it. every time I get a loaner rx350 I remember why I traded in.

 

I probably have the exact 2018 450hl you are thinking of buying. You will not regret the hybrid. My wife has a 2016 Rav hybrid, and it sold me on the hybrid versions. They are soooo smooth and have many other benefits besides gas mileage. You will not need to get new brakes for at least 100,000 miles. There are no alternators or a compressor, or other items hooked up to the engine. All of that stuff runs off of little electric motors. The benefits are too long to list, but well worth you time to learn more about the technology. The CVT has less than 20 moving parts compared to a normal transmission which has 100’s parts, needs maintenance and is never as smooth. The CVT does not have any belts or pulleys like other manufactures CVT, and does not need much maintenance. Get it—you will love it, and by the way I don’t put anything in but regular gas. I had a Cadillac a few years back, with a big V8, that was supposed to need Premium. I put 150,000 miles on it and never had a bit of problems with the engine.
I laterally drove it off the lot in September and the next day went on a 4000 mile road trip and never had an issue. Of course my wife was reading the manual to me as we were rolling.

 

From an outsider POV...

I recently had a couple RX loaners within a few weeks of one another. First was a RX350L which I had for about a week and then a few weeks later I had an RX450hL for another week.

For starters, both were incredibly enjoyable & relaxing vehicles to drive around in. Extremely quiet, smooth, comfortable, etc. All of my friends and family who got to experience them as passengers or as drivers also had really nice things to say about them and these weren't car people either. They usually don't talk about cars whatsoever. During my time with the RX's I came across a review where the reviewer stated that the RX has this desperate need to be liked by everyone and it gave me a laugh because it couldn't be more true. Not sure what it is but everyone who came across them, myself included, really enjoyed them.

That said, I enjoyed driving the 350, but loved the 450h. I loved being able to get in and drive away or drive through parking garages completely silently. The extra weight of the hybrid felt more planted and made the whole car feel a bit more heavy/solid and luxurious. I would take the hybrid's powertrain over the 350's any day. The electric motor torque combined with the smoothness of the CVT is really impressive and responsive whether you're passing or accelerating off the line. IMO, the hybrid not only makes the RX a more serene and relaxing ride but also more exciting. It feels like a beast in sport mode at freeway speeds.

 

My 450hl is my first hybrid but 5th Toyota product. I have about 6500 miles in it. Love it. It's everything you like about is true. I like tech and was always intrigued by hybrid technology. No regrets. My mileage is about 26-28 depending on the driving conditions. And unlike the non-hybrid, I get better mileage around town where it runs on battery more often and shuts down the engine. As far as fuel is concerned the Premium vs Regular has been debated to death and this site is not different. I run reg, mid and premium with no noticeable performance difference. The engine will just take care of itself by adjusting for lower octane fuel. In summary, no qualms running regular. Lastly, don't count on the 2 added seats to count for much. Adults for very short trips is realistically all their good for.

 

Pulled the trigger on the last remaining '18 RXhL in my region with the options/color combo the wife approved of! Was only able to get them to go $700 under invoice as they are covering the transportation fee by carrier to keep the mileage at 32 on the odometer. Could have gotten a 2019 for a similar price, but the 0% financing saved almost $3k based on current interest rates. Taking delivery mid-week.

Great to hear about the regular gas. Couldn't understand the logic behind a hybrid that runs on premium. Planning on keeping this RX for at least 150k miles.... Thanks all for the help!

 

Just to chime in I'm seriously amazed people put regular gas in these models. I mean sure, let's be honest Lexus has in the past gotten cavalier with octane requirements to achieve a better emissions rating (*cough* GX470) but generally speaking compression ratio is how you determine if it's needed or not. 9.3 to 1 and under and you are 100% safe to go 87octane (85 at altitude). 10.1:1 and you might still be fine, but you're starting to push the envelope. The 2018 RXHL is rated at 13.0:1!!! While the knock sensor *will* protect you, you are 100% dropping power in exchange for price per gallon!

 

There's a bit more to the story these days, which is why your reasonable compression ratio rules-of-thumb probably don't apply.

Toyota hybrids use an Atkinson-style engine design, not the traditional Otto-cycle. They do so in order to gain an additional 5% or so improvement in efficiency. Efficiency comes from having a very high EXPANSION ratio, such that the engine gets as much energy out of the expanding charge as possible before opening the exhaust valve. In a traditional Otto engine that meant having a high COMPRESSION ratio also (both were locked together), which meant too-high cylinder BMEP and engine knock. But in the Atkinson, Toyota leaves the intake valve open for part of the upstroke, so the total charge at the time of ignition is reduced. This means less power but, again, more efficiency. My 2010 RX450h engine has 240HP versus about 270 for its Otto-cycle cousin, but in the hybrid we also have electric motors to assist, so in fact the hybrid car has more total HP than the cousin. Very clever.

So don't look at the expansion ratio to see if premium fuel is needed. It's not. The engine is a whole different animal. And, as already mentioned, every modern engine uses a knock sensor that will kick in if necessary.

Car manufacturers use the "premium fuel" tag to maximize the specs and EPA ratings. As long as you use high-quality regular fuel, the engine will be perfectly happy but you'll lose a few HP and a fraction of an mpg.

 

If you say so, the Atkinson design mostly refers to the variable valve timings, which while they would allow a lower compression sometimes they also would allow the full compression at others.

I suppose based on your theoretical answer the only proof that would meet your needs would be measuring the knock sensor directly... While that might be a fun challenge someday (I'm sure techstream can log this) it's not worth my time as then someone will argue it's not valid for some other reason. Do what you will.