xjokerz

I've heard a ton of complaints about the harsh ride of the 2010-2015 RX. I definitely want a smooth ride, so would it be possible to put 17 inch wheels on this vehicle?

Apologies if someone already asked.

MattRX

I posted about it in the "Hard suspension thread". You would see better results getting a more comfortable tire or by installing Bilstein B4 struts & shocks from a Highlander.

Clutchless

You will be better off just replacing your tires with some that are noted to have a softer ride. That will make a big difference as ride quality varies a lot between tire brands & models. I suggest you do some searching at https://www.tirerack.com/content/tir.../homepage.html as they test most of the tires they sell and show the results of buyer surveys. You can also just call them up for advice. They have great prices and will tell you of local installers in your area. You can ship the tires directly to the installer. I have done this a few times and my local installer was a nearby Mr. Tire! They even did a nitrogen fill and a TPMS tune-up kit on my aging wheels.

Read the Hard Suspension thread listed on the main page, especially the last 5 pages in which someone thought his RX rode better with a couple of sand bags in the rear cargo area.

I also had Sachs 316603 rear shocks on mine for a while and they were a lot softer than the OEM rear shocks. They were too soft for me, but you will probably like them. A local gas station can install them in less than an hour. There are only 2 bolts on each shock, it is a simple job.
https://www.rockauto.com/en/catalog/...+absorber,7556