Definitely better for curb rashes, especially in the winter when the curbs are hidden and ice makes for a slippery roadway. 18" is the way to go.

 

I purchased 4 TPMS sensors ($32 each) on Amazon that were supposed to work on a 16' RX350 for my new set of 20" wheels (keeping my factory 18's for winter). I spent 4 trips to Discount tire trying to get them to pair up with my car. No luck, and finally had them pull the factory sensors from the 18's to put on the 20's. Anybody find an aftermarket (ie cheap) sensor that works?

 

OEM Lexus sensors are $57. CAD which includes the fit kit. That's about $40 us$.

Why would you go after market?

 

When I looked up OEM price (~6 months ago), they were $79 msrp. I'll try to find the for $40. Thanks!

 

​​​​​​
lexus pn for tpms valve is 426070E020
Firing kit pn 0442333060
The complete set is $239 CAD

 

I didn't know sensors were only $57 Can. I think I'll be getting some. I always thought they were closer to $100

Thanks Toyotaman7 !!

 

Hi there
Only two months into my new RX 350 and I need to get winter tires - can anyone suggest what choices I have for my 20" ? Want snow and ice tires.....

 

Toyo GSi-5 comes in a 235 55 20 if you are putting them on your stock wheels. Had them on my 3rx and loved them. Wear very well. Lots of other ideas in this thread....just look up. Toyotaman7 got a good deal thru the dealership.

 

Toyotaman - which dealer had this winter tire package? I'm waiting for my dealership to send me a quote but they never mentioned any package.

 

Just guessing that all the dealers have winter packages available.

 

My dealership called me back to tell me they highly recommend 20 inch rims and tires and not go any size smaller.

 

Dealers in Edmonton quoted the following, both on 18" sets of the base RX wheels complete with TPMS, mount, balance and TPMS programming:
Lexus South Pointe $2857, on Blizzak DM-V2
Lexus of Edmonton $3025, on Michelin X-Ice Xi-2

Not cheap!

 

Hi guys, new member here. Just thought that I would make my first post a little productive as people are now starting to put on their snow tires. I just got my new winter tires installed from my local shop this weekend. Went with Michelin Latitude X-Ice, 235/65-18 with new OEM TPMS sensors on new rims. I got the warning light on my dash concerning the TPMS within the first hour. Tried resetting the sensors but still have the warning. I called my sales associate to see if this was a problem when not using the original sensors. His response was:

1) The TPMS sensors have their own unique programming code
2) The RX 350 is only capable of have a single set of sensors programmed at any given time. It cannot recognize multiple sets.
3) A new set of sensors would have to be programmed for the car when the tires are changed. (Would be a chargeable service by the dealer if my tire shop didn't have the ability to reprogram the car)
4) The 'go-around' for this problem would be to buy TPMS sensors that can be cloned to match the originals.

Apparently, the dealership also sells these aftermarket sensors that can be cloned to avoid this problem with seasonal changeovers.
Also, there is no problem with using an 18-inch tire on the car. More sidewall and cheaper tire cost that using 20's in my opinion. I hope that helps some people before they start having problems when installing new TPMS sensors.

 

My dealership replied and sent me page 442 7.3 Do-it-yourself maintenance.
The notes read.

When inspecting or replacing tires. Observe the following precautions to prevent accidents. Failure to do so may cause damage to parts of the drive train as well as dangerous handling characteristics, which may lead to an accident resulting in death or serious injury

• Make sure to install four tires that are of the specified size, and that all four tires are of the same size, same brand, and same tread pattern.
• Do not use tire sizes other than those recommended by Lexus.
• Do not mix differently constructed tires (radial, bias-belted,or bias-ply tires).
• If only two tires are replaced, the new tires should be placed on the rear of the vehicle.

It goes on...

My quote from Lexus for four new tires: Bridgestone DMV2 235/55/R20. Includes OEM rims, sensor and labour. $3380.00 plus tax.

Tire storage service is $200 a year.

 

Well, I think there is one of two things happening.

1) Your dealership knows nothing , and doesn't realize that the base wheel/tire combo for an Rx 350 is 235/65 R18
2)The dealer is trying to rip you off because they think they can get away with it.

The main concern when determining the proper tire size on an AWD vehicle is the rolling diameter. The difference between 235/65 R18 and 235/55 R20 is 0.4%.....well within tolerance. The second concern is if a smaller wheel size will clear the brakes. I have an F-Sport with the original 20-inch wheels, and the new 18-inch rims definitely fit. I guess that it is up to you if you want to spend more for a larger wheel/tire combo that is not only more expensive, but also doesn't provide as much sidewall height.

BTW, my wheel/tire combo with new sensors was $2200 installed. I just called my shop, and they must have overlooked programming the sensors properly because they were super busy on Saturday when I brought the car in. I just have to drop by the shop and they will reprogram it. It will only take 10 minutes in the parking lot.