My Issues - Roof Rack Noise, Bad Hood, Fuel Capacity, Rear Dif Lock, Cruise, Brake and Brake System Noises

[R!ck]

I've had my GX550 OT+ for a couple months. It has 5000 miles on it now and 3000 of that is on the highway. There are a few things that I saw that In My Opinion are real design issues. I read the forums and see that other have seen them too. The first 4 were not apparent on the test drive because if any dealer lets you test drive one of these its a short loop around the block at low speeds. They all became apparent to me as soon as I had some time on the highway. So I'll start with those;

1) Wind Noise in the Cabin - Its unbelievably bad with the OT+ with a roof rack. I had it on highway with limits of 75mph and drove 80-85mph. You have to yell to talk to someone inside the vehicle. The sort term fix - take the roof rack off. I did it myself and once it's off the change is huge. They need to redesign the leading edge of that rack. It's not right as it is and we shouldn't have to remove it to have a reasonably quiet cabin at highway speeds.

2) Hood Flex - At highway speeds the hood flexes and bends a lot. The faster you go and the winder it is, the more you will see. The combination of flexing and reflections shifting around from the hood because of the flexing can be pretty distracting. I took a Lexus mechanic out today to show him today. That hood is not reinforced properly. The center of the hood looks like it bows up an inch or more, but you can even see it to a lesser degree in the ridges on the sides of the hood.

3) Fuel Tank Capacity - On the highway at 75-85 mph I was getting 15.4 mph. Less driving around home. A full tank shows me a range of 274 miles. This is a low range, really low for a vehicle that is designed for off road. I feel like that made the tank for the more fuel efficient Toyota 4 and never considered if the tank would be sufficient for the Lexus 6. 274 isn't even that good for an electric car anymore, so I can't understand how this was missed.

4) Cruise Control Calibration - I've been driving highways with adaptive cruise control in my car since 2002. The Lexus system works pretty darn well and is fantastic if you drive on the highways. Even the traffic jam assist (which uses the same system in stop and go traffic) is really nice. Whatever speed I set it at however, the car settles (when the road is open and the car is uninhibited from running to the limit) at 1 mph lower than the speed I set. I've played with it at different speeds, accelreting above the set speed and having it settle back down to the setting, changing the speed using the +/- buttons on the steering wheel, changing the safety gap up/down. It doesn't matter, it settles back to 1 mph less than what I've set.

Ok, those are my highway design issues. The first 3 are design issues. The 4th I am assuming can be corrected with a callibration. There are a few other issues that I am having them look at. They are;

5) Rear Differential Lock doesn't engage - I have taken it off the road, but it was light use on some frozen farm land. I am taking out into the desert next month. I have tried everything in the car just to know how it works. I've read the manual too. The one thing that just never worked was the Rear Differential Lock. I flashes and beeps but never locks. I showed the Lexus mechanic and they are looking at it now.

6) Brake Noise - The brakes squeal, mostly in reverse and after sitting overnight. I think this is a known issue and may have a fix already.

7) Screech when shifting out of Drive to Park - I understand that this noise from the engine compartment is the brake system and when I dropped it off for my issues today, I was getting the feeling that they were telling me that its normal and occurs on all Lexus. It's not normal for any other high car I've owned. At first I was causing the noise by slighting turning the tires on the epoxy finished garage floors as I was putting into park. That's what is kind of sounds like. Then I was worried it was coming from the turbos as they were spooling down (which would be really bad). Is this really something I have to get used to hearing when I park the vehicle?

I still really love the vehicle and can wait to get it from the snow of Chicago to the desert of Pheonix. I am hoping some of my issues have solutions that Lexus will be offering. If anyone knows of fixes coming, I would love to hear about them so I can "help" the dealer get them for my GX OT+.

I love the looks of the GX and was in line for one but I was concerned of a first year new model, even from Lexus just because Toyota is having so many issues now. I joined this forum to learn and discovered all the issues you mentioned and a few others. Like that ugly hitch cover which is awkward to say the least to use. And the 3.5TT issues Tundra and LX models are having. There has been no reported issues with the GX which uses the same engine but they are relatively new yet, really hope they have no issues. Other issues I’ve seen is cracked or chipped windshield’s, sounds as though there are no replacements available yet, probably first year issues. So as bad as I wanted one I couldn’t wait a year or two for little bugs to be worked out so I ended up with an Armada 2024 which that platform has been out there for over a decade. That probably makes it old school (low tech)but tried and true. Good luck and enjoy that new vehicle..

 

[Jabber]

I love the looks of the GX and was in line for one but I was concerned of a first year new model, even from Lexus just because Toyota is having so many issues now. I joined this forum to learn and discovered all the issues you mentioned and a few others. Like that ugly hitch cover which is awkward to say the least to use. And the 3.5TT issues Tundra and LX models are having. There has been no reported issues with the GX which uses the same engine but they are relatively new yet, really hope they have no issues. Other issues I’ve seen is cracked or chipped windshield’s, sounds as though there are no replacements available yet, probably first year issues. So as bad as I wanted one I couldn’t wait a year or two for little bugs to be worked out so I ended up with an Armada 2024 which that platform has been out there for over a decade. That probably makes it old school (low tech)but tried and true. Good luck and enjoy that new vehicle..

Despite my issues, I think the GX is fantastic. Almost all of my issues were ones that others had identified and all have pretty good resolutions. I've not heard of any systemic issues with the Lexus 6 turbo engine. So I am happy with my purchase and think it is the best looking true SUV on the market. I never mentioned the tow hitch cover, but it is ugly and I popped if off to leave the hitch visible. That looks the part on the OT+. Good luck with Armanda.

 

[jclaffee]

A couple comments regarding the parking brake....

Automatic transmissions are equipped with a parking pawl which is a metal pin that locks the transmission's output shaft, thereby preventing the transmission gears from turning, thereby preventing the wheels from turning.

The parking pawl is considered a backup to the parking brake. You really shouldn't rely solely on the parking pawl keeping your 5,500 lb truck from moving. When you look at a scene such as cars and trucks parallel parked on steep inclines like you see in San Francisco, it should scare the shit out of you knowing that the vast majority of them probably have no parking brakes engaged. But at least it's not like the ground would ever shake in San Fran and put extra stress on all those parking pawls....LOL.

The practice you should actually observe is to drive to your destination, parking spot, etc., put the truck in (edit - neutral not DRIVE), keep your foot on the brake pedal, activate the parking brake, then shift into park. This puts the task of keeping the truck from moving primarily on the parking brake with the parking pawl as backup. This keeps the stress off the transmission components.

I don't know if the GX550's fancy automatic parking brake does anything special, such as making the parking brake the primary and the pawl the secondary. I'll just leave it on automatic and let it engage each time I shift to park.

As an old friend used to say about the parking pawl, it's not a kickstand.

Regarding parallel parking on hills, I'd add some additional insurance - Park tight against the curb and turn the wheel hard so the front tire will make contact with the curb immediately if the vehicle were to roll (so turn toward the curb if you are facing downhill, away from the curb if facing uphill). Basically free wheel chocks.