What advantage/disadvantage is there one over the other?

I would assume the 19" wheel would wear better.

Cheers!

 

Seems there is more selection of tires in the 18 " and/or potential differences in costs for 18" vs. 19" tires (18" being cheaper to purchase in some brands). Would seem that wear differences for 18 " vs 19 " would be negligible.

 

18" tires are ~$50 cheaper each

18" will run 60 series tires. the extra sidewall should make for a smoother ride

19" will run 55 series. shorter sidewall should corner better

 

19" might not be as smooth of a ride vs the 18".

 

With everything the same, tire brand, pressure, driving condition, wheel alignment etc.
the higher you go with rim size, the stiffer the ride.
that's why the loaner with a basic 18 inch rim rides softer and cushier than a 19.

 

I drove both and I thought the 18" were slightly softer and had a smoother ride. However, 19" were Dunlops and 18" were Michelins so it could have been tire brand more than anything.

 

you're right, the 18 is softer and smoother.

 

I have BOTH. The 350 is 18" on 60 series and it is softer while the 450h is 19" on 55 series. If I can do it all over again I will go with 19" on the 350 as well. Expect the 19" tires will wear out faster, but not too much though.

 

Curious - are you saying that the "less soft" ride on the 450h with 19" is an advantage - better handling etc?

Also as an owner of both RX, can I inquire as to the relative MPG you get on the two?

Thanks!

 

^19" are heavier hence the less life in thread, also MPG is less due to it's weight, prolly not that much. 19" looks better than 18". And I always thought that softer tires handle better than stiffer ones.

 

now, what pressure with your tires 18' et 19' ?
Personnally, when I have to drive with familly et luggages, I put 3bar maxi (less friction, less consumption and a bit stiffer but sounds very good for every body).
Otherwise between 2,7 and 2,9. I do this for many years with my cars and did not experience any problem (parallism still perfect, less consumption, less emission, less noise in the car).

 

Alpy, it's usually just one person and me so on 19's I run about 33-34 psi (2.3 bar). 3 bar would be too harsh for me, but I could see fully loaded you might want that. On some of these poorly constructed roads, I don't like feeling every crack or control joint.

 

I don't think it handles better or not since my RXh on 19" is heavier than my spouse's RX on 18". I can't also tell you the MPG neither since one is hybrid and one is not.

RX350 - Ave on highway between 70-80 mph is 23-24 mpg
RX450h - Ave on highway between 70-80 mph is 27-28 mpg

City MPG is a big different, 18-19 on the 350 while 28+ in 450h.

 

Isn't it national known that high breds are better in city driving, but not that great in highway driving??

 

Yup. I think I can get over 28+ MPG on highway if I keep it under 65 mph (I think that is the speed they tested with) but when it hits 80 mph the mileage drops big time. Also, winter months are bad for gas mileage.