My daughter is the family’s designated driver, and a fast driver. She hits 80+ every time she gets on the freeway if it at all possible. Except when Mom is in a bad mood, then she hits only 80. I don’t know how fast she drives when she drives by herself, but I imagine 80+++.

We’ve never noticed any vibration.

It’s a 2020 RX-450h F Sport.

 

I have tried 3 different tire shops. The problem was in balance. You won´t believe but Lexus dealer do not know how to propper balance RX wheels and also some other shops. I finally found a shop based on customer reviews and gave them a try. Wow they did a great job.
So good luck. It tooks me almost 1.5 year to solve those vibrations. Lexus dealer took a car for a five times or so. They gave me a new tires too. They connected computer + wires all around the car and drove fast to find from where the vibration comes from.
Last time when they gave me a replacement car (same car RX450h) I have drove home form dealer and noticed that there are also vibrates on that car. So I found what is the problem, they have to have bad balance machine...

 

Road force balancing will usually do the trick and in my case, it was ONLY my Lexus dealer that was able to resolve a similar issue I had with brand new tires.

 

Balance, balance, and balance. If tire was "balanced" in one shop it does not mean it actually balanced PROPERLY. The machine could be off and so forth. Once it took me a long time to find a good shop that does it.

 

I think you ought to rephrase....THAT lexus dealer rather than Lexus Dealers.
Obviously your dealer did not have the proper equiment like a balancer with road force or if it had it it may not have had a mechanic proficient in operating it.
I found my dealer utterly competent in all things pertaining to the car.

 

Wow, thanks for all the feedback, I have a clearer next step!
Next step: balance all 4 again, at a good shop. (I went to $8 a wheel local shop last time, which was never an issue)
If that still doesn't solve the issue.. either they are still unbalanced, OR my dad messed up the half shaft in front/rear/both and didn't tell me, OR it's a defect in the RXs...

 

There is one more thing, your tire(s) may be out of round and a good balancer w/road force with a good operator may lessen the problem, but if really out of round there is only one remedy and that is replacing the tire(s).
I don't think that I'd go to a $8 a wheel to find the solution though.

 

Thanks Cocal! I never thought about the tire being our of round. That could be the issue too. Thanks!

Yea, the $8 balance is good to cheaply find out if it was just a minor balance issue. Which this isn't!

The stealership said they wanted $190 for an inspection fee to check it out. I probably won't be doing that.

 

That's insane, but a good balancer w/road force will cost around $100 as it requires more skill and the machine is more expensive,

 

The question is, did your installer do a good balance? I have personally done wheel balance and watched the people who work on my cars. Most don't do it right and it leads to vibration. At $8/wheel (which is very low), I would bet they didn't take time to do it right.

What most shops do is spin it once and slap on whatever weight it asks for, then call it a day and give it back to you. If they're big truck tires, shops might even spin it again to get it closer. But rarely ever do I see people who repeat until it asks for no more weights (0.00 on both readouts) and therein lies the problem. It can take 4 or 5 spins, especially on these new cars with huge 20" wheels. Since there is no printed final readout, you would never know whether they spin it once or spun it 5 times. Not only that, but some shops told me they only used the Road Force balance on bigger tires.

If the installer spends 10 minutes per wheel to get it off, mounted on the machine, spin it a few times to get it perfect, mount it back on the car...they're not making any money at $8/wheel, which is why I suspect your problem lies there. All that road force balance is great, I thought that was the silver bullet, the one and only fix. I started searching out shops with Hunter machines. I didn't bother to watch them because of these state of the art machines, but the vibrations persisted across several cars. I seriously thought about changing out suspension and drivetrain parts. Finally I found a shop that cared and also used the road force balance, and voila, came out perfect. Smooth as a whistle up to uh...we'll say 65 in case anybody is listening. Sadly, these shops are few and far between. I've tried Costco, small independent shops, large chains, dealership service departments, multiple cities across CA while I was on vacation, and only found ONE shop who did it right the first time. The other bad balances, I just lived with...

 

Yea, strange, I never had such an issue with balancing (if this is the case here)
Mechanics can be an art, and all about the details, and not everyone can do it "Really Well"... unfortunately.
Saddest part about this is my Go-To guy closed up shop before pandemic, so I lost my 1 guy that I had been trusting with all my cars. I'm super picky too, considering I do my car work when I had the time.

 

Side rant: working on cars can be an artform, and all in the details sometimes... Do you guys feel the same with with doctors and surgeons? There's a ton of them, but you don't really know what they do under the hood unless something breaks again or you die and take the bad work to the grave.. lol

 

I've had a few Drs that probably should work on cars instead

 

After a long time, I found out it was the tires. After replacing the tires, the vibration is pretty much gone. I thought I'd give some closure

 

Pretty much gone? Stay with it and get it done right. I have taken my RX back multiple times to Discount Tires before issues were resolved. There should not be any vibration. Discount Tire told me once that Lexus vehicles are hard to get right unless the balance is dead on. My last set of CC tires were from Discount Tires in Denver and after they were installed, I then went on a 350 mile road trip to Santa Fe and the car was vibrating at any speed over 50. I took it to Discount Tire in Santa Fe and told them the issue, and while the tires were being rebalanced, the manager came to me and apologized for the balancing job done in Denver. He indicated that on one tire there was mud on the inside of the rim and under the mud was the original balance weights. Denver had just put more weights on the rim and not removed the mud or the original weights. The tires were perfectly balanced in Santa Fe.