Swacer

Eek....I don't even consider those two as actual companies.

Cheap, half #(%*$ designed cars. I had a genesis coupe for a short time right after I graduated college, and it was a joke and a maintenance nightmare.

LexBob2

They're not everyone's favorites, but they are now mainstream brands and sell a lot of cars. I'm surprised they've kept their long warranties, but it is a selling point. Agree that their reliability is still spotty.

01LEXPL

iTrader: (10)

The EX/ES use a completely different motor with lower compression. Instead of a Turbo-4 they run a smooth V6. It does not need the fuel properties of high-test to run efficiently.

Good on you for using premium, it burns cleaner anyways [less solvents/additives put into the 91+ fuels, unlike 89 and below]

LOL! People should seriously stop this nonsense, I've seen it on here so many times over the years. You have people in IS' running 87 "because it runs fine" - those are the people with lease vehicles, so they can care less what happens down the road LOL jokes on the dealer.

If anyone in this thread actually owns [financing to keep] their NX and running 87 when the gas cap stipulates otherwise, well, they're gonna have a bad time [down the road]... as you said.

I currently drive a turbo subaru and I wouldn't dare run anything other then premium because it can do serious damage, let alone drivabilty.

It seems asinine to consider anything but 91 in the NX, since it is; turbo, and if the car was tested and RATED at 91 by the manufacturer and EPA, you'll have the same people trying to cheat with 87 being the first ones to cry about getting 18mpg instead of 20mpg, because they saved 5$ at the pump once a week, instead of getting 5$ more of mileage without potential adverse effects on the motor in the long run.

It's a losing battle arguing about which fuel to use. All it takes is one guy to get away with [like the above Lease IS example] and sheep will flock, fight tooth and nail that they too can get away with it... but be the first to complain and call Lexus customer care when their car is getting 2mpg less or breaking down because they couldn't follow the gas cap.

Good on them. The way of the turbo motor is evolving, coupled with direct injection and CVT transmissions.

Keep in mind this is Lexus' first foray into the [compact, fuel efficient] turbo world.

Also those two brands aren't good examples, since they do not have any resale or worth once they're a few years old, unlike lexus which has the best resale and sales year in & out.

Hell, even Subaru which has always been working with [only 91+] turbo's has now introduced the option to its owners in the 14+ cars in the manual stating that someone can run 87 in their car, AT THE COST OF MILEAGE AND POWER...

Perhaps Lexus should have incorporated that into the NX manual, if I and others are completely wrong and the NX can fully support 87...

Joeb427

iTrader: (1)

Hard to believe because the certain Toyota models with the 3.5L V6 is the same 2GR-FE since '06 as Lexus premium fuel 3.5L V6 models before the going down to 87.
4 less HP and a bit less torque with 87.
I don't think they changed anything but the fuel requirement.

Just Googled and a 2012 Camry has a Compression ratio: 10.8:1
Same compression ratios in a '07 to present ES350.

Swacer

Thats only assuming they are willing to warranty it. After my 3rd failed transmission in a single summer, they tried to avoid replacing it.

01LEXPL

iTrader: (10)

I'm not arguing the 2GR here, I was responding to make a point regarding what can run 87, ie. the 2GR and that a turbo motor should not be running the same fuel type due to compression difference.

I think you misread my reply. I'm more than aware of that V6, it's like it predecessor which was the 1mz from the 90's that was tweaked over the years until they switched to the 2gr...

Joeb427

iTrader: (1)

I agree running Premium in the NX turbo is the only way to go.

Rdcrow

I'm spending less on gas putting 91 into my NX than I was when I was putting 87 into my RX. Doing the same amount of driving.

corradoMR2

87 tank completed two days ago and filled it back to 91.

Result: No discernable performance and sound difference.

15RC350F

In addition to our NX 200t we also have a 2015 Genesis Sedan, loaded. Dealer was outstanding, it has features that would have cost $10-15K in a comparable model from another manufacturer and it rides like a dream.

Swacer

Give it time....it will show its a Hyundai. Keep in mind Hyundai and Kia brag about their initial quality. You NEVER hear talk about their reliability. That's for real companies, like Honda and Toyota to talk about.

But since you had to mention you have a "fully loaded Hyundai", you get my story. When I had my "fully loaded" 2010 Genesis coupe (second mirabeau blue 3.8 track model stick in the country) it started out great also.

Lets start the list since you've indirectly asked....

1. Window Motor fails...3 months into ownership
2. ECU fails..car dies.....6 months into ownership
3. Hood is bent and not flush to the headlights on both sides....6 months into ownership it is noticed...dealership claims I did it until I show them that EVERY car in their lot has a hood like this. Their solution..bend my brand new hood.
4. Tail lights leak in the 1 freak rain storm I get caught in.....10ish months into ownership
5. Headlights fog when on....they spray my car, which never saw rain with a hose and since it only "fogs severely" but doesn't accumulate water...its not considered replacement worthy.
6. Transmission #1 - 15 months into ownership....2nd and 5th gear grind...replaced without question
7. Transmission #2 - 2 weeks after #1 - driving down ohio turnpike, I can feel flywheel in my hand. I took the car immediately back to the dealer and was told the shifter nearly sheared at the transmission.. They fix shifter and 2 days later the 3rd gear syncro fails. Hyundai has the audacity to inquire to the dealer if I was racing the car since the failures were 200 miles apart. After my dealer confirmed I've never hurt the car (dealer was great, just can't help a piece of crap car), their "engineers in korea" (who I shall refer to inferior morons), had the nerve to say the syncro will work better with a LOWER viscosity fluid. Since I had no say in the manner, they took my car out onto a main road to test their theory...guess what...they blew my transmission up and had to tow the car back.
8. Transmission #3 - 2 weeks after #2 - 5th gear has a bur in the gate and will sometimes not leave the gate.
9. Window motor fails again....

And lets also keep in mind, the same time my car was there, my local dealer had 2-3 Genesis sedans in the shop for similar issues to mine. And you "could" say that I am a 1 off lemon, but I have an entire forum where we all used to keep track of "dealership visits and driving days lost"

I got rid of that car with 15k miserable miles. Dumped it in October and ordered my camaro in November. Been a dream ever since. Plus, when I shut my door, it doesn't sound like cheap sheet metal like the genesis did!

If you want a further example, my mother had a "fully loaded" santa fe. Lasted 90k miles, but not without multiple transmission failures, ECU failures, and ridiculous amounts of rust. While the warrantied the tranny and ECU, they felt it wasn't worth looking into the rust. That car died on the side of the road.

And this is with a family who builds race engines and knows how to take care of cars. I can only imagine its worse for people who trust the dealers.

There is a reason the car was $10-15k cheaper than the competition.

Fizzboy7

There are two distinct tiers to all of this. The 2.0t engine that can safely run on lower octane without damage and the 2.5 V6 that requires premium and risks problems later on with lower octane.

So here is my big question. Do manufacturers do more mechanical changes to separate the "91 octane only" engines from the "91 recommended" engines? I know timing and spark is changed on all motors when lower fuel is used. But I was under the impression there's even more work done to help protect a motor when the manufacturer claims it can run on lower octane with reduced performance (but without engine damage). The ones that claim "91 only" do not claim lower octane won't damage things. So what do they physically do to the engines to enable them to safely run on the lower octane and differentiate between the two tiers?

Swacer

For engines that recommend 91, it means that the engine is at its peak performance and optimum location on the fuel tables at 91. However, there is enough give in the tables to allow for a lower octane to be used and prevent knock.

For an engine that is 91+ only, it means that the engine is running at a high enough compression (typically a boosted engine or an engine like my camaro in which the fuel tables were intentilaly updated to run 91+) that the fuel tables can not allow a lower octane without the engine knocking and potential impact to long term engine life.

You typically see this in the following ways:

Boosted Engines - Typically are required premium

Small Displacement making High Hp for the size - High Compression = premium required

Performance engine making big hp - High Compression = premium required

15RC350F

Sounds like you had a bad car. But it was five model years ago.

We traded in a 2003 Kia Sorento (also loaded) for the Genesis. That SUV had but a single problem its entire life: when it was two weeks old someone broke in and stole the stereo, breaking up the center of the dash pretty well. Insurance took care of that.

I will keep you posted should we have any issues with our Genesis.

Swacer

"Sounds like you had a bad car." Didn't read that part about the gencoupe forum, huh?

I wish you luck with your car and hope it doesn't give you issues.