great friend ,you owe him a beer

 

Looking into tire vibrations a little deeper. There is a much superior tire balancing system which I hope was used the last time you had them balanced. It's actually a specific Balancing system or machine called Road Force made by Hunter.
https://www.hunter.com/en-ca/wheel-b...rce-elite/#roi



This is exactly how wheels are balanced at the factory. You may have had something happen to your tire(s) possibly before delivery. Watch the video for a good explanation on how this works. If the wheels have been correctly balanced with this method and your shop confirms that the balancing machine has been calibrated recently (Yes the need to be checked regularly. I'm not sure how often, but they will go out of calibration) then you have probably eliminated any vibration coming form your rim tire assembly. One huge key benefit is that a roller contacts the tread surface of the tire to determine how much 'out of round' exists in the rubber tire and rim. And YES every tire and rim has some runout. The roller also is applied with 'Force' so that it replicates a load on the tire (watch it squish the tire a bit in video). The plys in the construction of the tire may also cause a vibration when rotated and the tire is loaded, but the tire won't be out of balance per say!
I always ask for this type of balancing when replacing my tires and even if for whatever reason the tire is removed from the rim I ask for this type of balancing. It has always solved any slight vibration I've had with highway speed vibrations. I learned about this type of balancing after having a set of 4 tires replaced at a nation wide tire shop, did some digging and went back to ask them and guess what they didn't use these types of balancers! Went to another shop that had it, paid the 'extra' cost to do this Road Force balancing and ride was smooth as a cucumber, you couldn't even see any ripples in a cup of liquid sitting in the cupholder going down the highway!

The reason why a lot of tire shops don't use these machines is they're expensive to buy and maintain. Dealerships though typically have them as they're usually mandated by the Manufacturer to use these types of machines for their tire servicing. Plus as we all know rims and tires are extremely expensive and having to work on them need to be precise work! To avoid scratches, damage to tpms sensors, bead damage etc., plus rims and tire are getting very large with 20 + inch diameter rim sizes being used and very wide treads.

 

I'd like to thank everyone for their input and suggestions for what could be the cause of my vibration issue. And, yes, at 4500 miles it still persists. I've also started to notice a bucking sensation at low speeds around 10-20 mph.
At my request, I drove a new NX 350h this week to see how it compared to mine. I didn't experience any of the vibration issues that mine has. I asked the service manager to drive my NX, she declined. I don't know if she wouldn't or couldn't...maybe she's not allowed to leave dealership. She told me there's nothing she can do for me and that I should call Lexus Customer Service.
I already had a case number open through Lexus. I'm requesting for the traveling technician to drive my car with me. We'll see what happens.
I'm a bit outraged at how I've been treated currently. I don't enjoy driving my car much anymore.

 

I feel for you RX350ok. Seems she's just pushed you off to the Lexus Customer Service line.

Would you happen to have another Lexus dealer you could go to that is more willing to help.

I would make that call to Lexus Customer Care and let them know that your concerns have not been handled to any high standard you would expect coming from a Lexus dealer. You're not imagining this and want it taken seriously, this may have occupant safety concerns ultimately, if not diagnose and corrected.