Our 2010 RX350 has been a beach-goer on North Carolina's Outer Banks for the last few years. I'm reticent to post this because of the large number of posts about OBX beach "idiots." Simply put, I'm looking for advice on tire sizes that can get me a little more clearance on the sand. The oem 235/60/18s give barely enough. I occasionally drag the undercarriage, which doesn't worry me too much on sand, but, at this juncture, every inch counts. Tire sizes out there that would give us and inch, or inch and a half? No offense to the "Corolla Beach Idiots" page, but the we're going to keep rolling the beach without TRUE 4WD.

 

I don't think this has been asked before and I don't have a direct answer - how large a tire can you put on the 18 inch wheels to drive on the sand?
Most folks who go larger also get larger 19 or 20 inch wheels but keep the overall circumference close to stock.
Do you intend to do much street driving too? That large a tire will throw off the gearing, speedometer and acceleration etc and you have to worry about suspension and body clearance. The folks at tire rack may be able to help and you may be better off getting a dedicated set of wheels & tires for beach driving season.

Look at the tools drop down menu on the black menu bar at the top of the main page for the tire size calculator.

I did find these olds thread about 245/65/18 tires. Some in it have used 255/55/18 tires.

https://www.clublexus.com/forums/rx-3rd-gen-2010-2015/677595-new-tires-245-65-18-done.html

https://www.clublexus.com/forums/rx-3rd-gen-2010-2015/788189-larger-tires.html

https://www.clublexus.com/forums/rx-...on-rx450h.html

I'm heading down there next week and maybe I will look for an RX on the beach!

 

This was on the beach in Oregon with 255/50/19 all season tires. Getting onto the beach involved going through some deeper dry sand but got through it with enough speed. As shown in the picture, the sand underneath the vehicle at this point is damp and harder packed. I've since replaced those tires with 235/55/19 and have been back on this beach with no difficulty getting through the sand.

 

When driving in loose/packed sand beach area, isn’t there concern about sand getting trapped precariously in wheel, brake, moving joint, etc. exposed areas in the undercarriage?

 

Yep, but all of that can happen on dirt roads just as easily. You have to thoroughly hose off the undercarriage from time to time.

 

I wish Hatteras Island had that kind of hard-packed sand! I've had little problem starting, and stopping, it's just the clearance. The belly gets dragged in some of the softer, deeper stuff, I'd like to avoid that. The folks really do stop and stare at our RX on the beach. It's like they're watching aliens do something outlandish.

 

I've done some research, I guess it's just a matter of finding what will fit under the RX. The Pirellis I have are about 29.5 inches in diameter in 235/60r18 according to the literature. A newer Pirelli in 245/60r18 is only 29.6 inches in diameter, as is a Falken Wildpeak A/T. A Cooper Discoverer AT3 4S in 255/70R18 is 32.1 inches tall. It seems difficult to find something in between, and 2.5 inches seems like a big jump, especially for gearing, and fitting inside those wheel wells. Long story longer, anyone ever go that big?

 

255/50R19? Didn't it come with 235/55R19 originally?

 

Yes 235/55/19 was and is the original tire size.
Going to 255/50/19 works better with wider wheels as it gives the wider tire more room to spread out. I have 8 inch wide wheels. 8.5 inch should also work.
The original wheels are 7.5 wide.
255/50/19 is almost the same diameter as 235/55/19.