Q70L 18 inch vs 20 inch tires

[emanon]

I just purchased a pre-owned 2015 Q70L (it only had 17,000 miles!!) that has 18 inch tires. I really like the look of the Q70L's I've seen with the 20 inch tires. How is the ride comparing the two? Is there something I should be aware of buying 20 inch tires?

[Ilya]

Welcome to the forum.

Less sidewall = more feel when hitting a bump = higher chance of bending a rim. Otherwise nothing really else changes.

[emanon]

I don't like the feel of hitting bumps. Therefore you have greatly helped me. I will keep my 18 inches and powder coat the rims. Thanks!!

[DKASM37]

Going from the stock 245/50/18 to a 245/40/20, the change in ride quality will not be anything significant. Mine came with the stock 18” Michelin Primacy mxv4’s and I went to 255/30/22 Continental Extreme Contact DWS-06’s. The comparison in ride quality between the 2 are practically identical to each other. It all depends on how much you want to invest in your tires, that makes all the difference. Plus, the Continental Extremes have a reinforced sidewall. If you like the look with the 20” wheels, go for it. In my opinion, the car is too big to ride on 18” wheels. My 2 cents...

[satown210]

Less sidewall equals harsher ride and more noise. It's a trade off. Looks better, rides worse.

[Ilya]

The ride and feel is subjective...everyone has a different take. But generally speaking, less sidewall = more feel of road imperfections/noise.

[Dark_Knight]

Going from the stock 245/50/18 to a 245/40/20, the change in ride quality will not be anything significant. Mine came with the stock 18” Michelin Primacy mxv4’s and I went to 255/30/22 Continental Extreme Contact DWS-06’s. The comparison in ride quality between the 2 are practically identical to each other. It all depends on how much you want to invest in your tires, that makes all the difference. Plus, the Continental Extremes have a reinforced sidewall. If you like the look with the 20” wheels, go for it. In my opinion, the car is too big to ride on 18” wheels. My 2 cents...

You gain 2" of wheel and lose about 1" of sidewall, it sounds like a decent trade-off. I agree that the 20's look better than the 18's on these cars because of the amount of space in the wheel well.

[GMBQ70]

Understanding the topic is 18 vs 20. But the Q70L on 20’s performs better than the “regular” Q70.
I drive a Q70 with 20’s and we recently purchased my wife a CPO 2017 Q70L, which is also on 20’s.
After driving both for a few months now, the L is a much smoother ride and not quite as much feel or feedback from the road as my non L Q70.
Congrats on the new ride & enjoy!

[emanon]

Ok you all almost have now convinced me to get the 20’s which is what I really want!! Maybe I can go to the dealer and test drive a Q70L with the 20’s and see how it rides.

[Johnny Means]

I have 18s for my winter tires and 20s for summer. Anyone who thinks ride quality doesn't suffer dramatically is either lying to themselves or not very critical. On the other hand, handling does improve dramatically with the 20s. As an example, railroad tracks that I don't think about at all with the 18s sent me to the wheel shop with two bent rims with the 20s.

[emanon]

Oh no!! Not bent rims!

[austin713]

i went from the stock 18s to the 20s and not only is it the number one complement i get on my car, but it completely changes the overall look and gives you a bit more steering feel since you no longer are riding around on marshmellows. i did not notice any real change in ride quality. TBH the stock ride is a little bit too floaty for me anyways so it was a welcome change.

[Malbec 56 Beast]

I think this car and the size of it needs 20's, The factory size of tire is a 245-40-20 but I am running 275-35-20. They feel great. BUT PLEASE choose a nice wheel, take your time and look at what is out there. Don't choose and ugly wheel.

good luck

Andy

[emanon]

Ok I had 20 inch wheels and tires installed today and drove on the highway. The ride is more smooth on the 20in than the 18in that I replaced. The car felt like it was more gripped to the road and I didn't feel the rough spots. However, what really surprised me was the gas mileage. I thought it was supposed to be worse with the larger tires. It wasn't. I was getting about 19 miles per gallon with the 18in. I am getting 22.5 with the 20in. I am surprised.

[Larz]

I agree. Technically, less sidewall = more road 'feel' and increased road noise. However, nobody can tell you exactly how MUCH of a difference. That's where we, as individual snowflakes, come in. I know that when I went from the stock 245/45/18 to my current 255/40/19, the wider tire, decreased sidewall, and larger wheel definitely DID change the feel of driving and road noise. I don't notice any more road noise to my ears, but the grip in rain and at high speeds is absolutely EPIC, compared to stock wheels / tires. That's another VERY important point ... TIRES! If you buy low or ho-hum quality tires like goodyear, goodrich, cooper, you aren't getting the most out of your drive. In those cases, maybe changing wheels or tire size will make a noticeable difference in noise because you'r using bargain tires to begin with.
The only tires that I would ever consider are Pirelli or Michelin. I know people like Continental, but they always perform worse in tests than most other similar priced tires.
If you stick to the category called "Ultra High Performance", you will get the most from your driving. I won't buy a tire that isn't in this category. Go to Tire Rack, see the list, watch the test videos. Wait for a sale. If you get your wheels from Tire Rack, they will mount your tires for free, high-speed balance them for free, include free road hazard repair / replace, install new TPMS, and ship them to you, or whomever you want to install them. Mine arrived at my dealer in 3 days. All I paid for was install and alignment.

[emanon]

I agree. Technically, less sidewall = more road 'feel' and increased road noise. However, nobody can tell you exactly how MUCH of a difference. That's where we, as individual snowflakes, come in. I know that when I went from the stock 245/45/18 to my current 255/40/19, the wider tire, decreased sidewall, and larger wheel definitely DID change the feel of driving and road noise. I don't notice any more road noise to my ears, but the grip in rain and at high speeds is absolutely EPIC, compared to stock wheels / tires. That's another VERY important point ... TIRES! If you buy low or ho-hum quality tires like goodyear, goodrich, cooper, you aren't getting the most out of your drive. In those cases, maybe changing wheels or tire size will make a noticeable difference in noise because you'r using bargain tires to begin with.
The only tires that I would ever consider are Pirelli or Michelin. I know people like Continental, but they always perform worse in tests than most other similar priced tires.
If you stick to the category called "Ultra High Performance", you will get the most from your driving. I won't buy a tire that isn't in this category. Go to Tire Rack, see the list, watch the test videos. Wait for a sale. If you get your wheels from Tire Rack, they will mount your tires for free, high-speed balance them for free, include free road hazard repair / replace, install new TPMS, and ship them to you, or whomever you want to install them. Mine arrived at my dealer in 3 days. All I paid for was install and alignment.

OK Thanks!!! I did buy some highly affordable tires just see what a 20 inch ride was like. I am getting this great ride from Hankook tires! The Infiniti dealership was selling buy 3 and get the 4th free. So I decided to try. I'm so surprised that I don't get a great deal of road noise but I can imagine it could be better. I will keep these until I see a great deal on "Ultra High Performance". Then I will sell the Hankooks.

[Larz]

OK Thanks!!! I did buy some highly affordable tires just see what a 20 inch ride was like. I am getting this great ride from Hankook tires! The Infiniti dealership was selling buy 3 and get the 4th free. So I decided to try. I'm so surprised that I don't get a great deal of road noise but I can imagine it could be better. I will keep these until I see a great deal on "Ultra High Performance". Then I will sell the Hankooks.

I tried a set of Hankook Ventus S1noble2 tires previously. Here is my thread about them: post6574098.html?hilit=hankook%20s1#p6574098
They were amazing when new and for a long time after, too! I went back to Michelin because the road noise after a half tread life was passed, became annoying. They still performed great, just got noisy.

[emanon]

OK Thanks!!! I did buy some highly affordable tires just see what a 20 inch ride was like. I am getting this great ride from Hankook tires! The Infiniti dealership was selling buy 3 and get the 4th free. So I decided to try. I'm so surprised that I don't get a great deal of road noise but I can imagine it could be better. I will keep these until I see a great deal on "Ultra High Performance". Then I will sell the Hankooks.

I tried a set of Hankook Ventus S1noble2 tires previously. Here is my thread about them: post6574098.html?hilit=hankook%20s1#p6574098
They were amazing when new and for a long time after, too! I went back to Michelin because the road noise after a half tread life was passed, became annoying. They still performed great, just got noisy.

I figured at about 1/2 the tread the Hankooks will get noisy. You confirmed what I was thinking. So I plan installing Michelin at that point. If I find a buy 3 get 1 free kind a deal on Michelin, I will switch out before 1/2 the tread is gone.

[kmiles]

For 18" tires - there are not a lot of good options for the stock 245/50/18 size. It looks like the Pirelli P Zero All Season Plus and the Continental Extreme Contact DWS06 are the only decent high-performance all-season choices. The only tire dealer in my area that sells them is not one that I ever want ot use again as they kept snapping off bolts due to over-torquing. I did a lot of online searching and couldn't find anything on what other sizes will fit on the stock 18" rims. Will a 245/45/18 fit? I would really like to move to the Michelin Pilot Sport AS/3+, but it does not come in a 245/50/18. What issues would this cause, if any?

[Larz]

The 245/45/18 will definitely fit but ever since my first set of 255's I will never go back to 245's. I always use Tire Rack and they can deliver to your home, your dealer, or any tire shop you choose - takes about 3 days. I love my pilot sport A/S 3+ tires. They grip like glue even in the rain. They are not silent, but very quiet on the roadway and the handling response is amazing. I would recommend 255/45/18 for your car. That gives you a slightly wider track for even more grip and handling with no change in the 'ride' quality. Tire Rack has them with a $70 rebate on a set of 4 255/45/ZR18. They are rated at: 500-AA-A which is the highest standard for tread life, traction, and temperature stability. The latest test they did places the Pilot Sport A/S 3+ and the Pirelli P Zero at the top of the pack and, as usual, Continental falls short for wet handling and steering response. The Michelins are $749 for a set of 4.

[kmiles]

Thank you for the reply Larz! I dropped by my local Costco last night to see what they would install as they have fairly tight policies on what they will install on factory rims. The tire manager said that they couldn't sell and install 255/45/ZR18's on my rims/car, but they would install 245/45/ZR18's but asked me to contact my local Infiniti dealer to see if they would cause any issues with the ABS or AWD system.

I remember reading in the past that you're a big Griot fan. I dropped by their HQ store in Tacoma on my way home from Renton last Friday and they came out and looked at my car and gave me some recommendations on how to detail it to get it to a showroom state. I spent about 7 hours on Saturday working on the exterior surfaces and ended up with a beautiful car when all done. I found one small scratch that I couldn't buff out and a small rock chip that required some touch-up paint. The Hermosa Blue color looks awesome on this car.

[Larz]

Glad to hear! I have never been disappointed with any Griot's product and my car (9 years ol and 104k miles) still looks better than the new cars in the showroom! The Griot's BOSS system polishes and Sealants make the surface and color look soooooooooooo deep, like the finish on a Bentley or Rolls. And the leather is softer and more pliable than the original condition. Griot's is only slightly more expensive than Mothers or other car parts shop brands, but the results are staggeringly better.

[Ahmadnakhlah]

I recently purchased a 2015 Infiniti q70 , it came with the stock 18in wheels I decided to upgrade to the 20in q70 sport wheels but came across a problem. I balanced the wheels 3 times the 3rd time Firestone thought throwing in balance beads in each wheel will fix the balance and told me to give it 3 days for it to kick in . I took it there Saturday and it’s now Monday and I still feel the shake in the steering wheel going over 60 mphs anything under that it drives very smooth . Also it’s sitting on Toyo tires so it shouldn’t be the tires fault they’re brand new . Before taken it to firestone I took it to a couple other tire shops and they had told me they wouldn’t balance my 20in tires just cause it’s hard to get them balanced . Anyone know what I should do next ? Thanks

[AZhitman]

Any shop that won't balance 20" tires is staffed with clowns. 20" is very common, and not hard to balance.

My suspicion is a bent wheel, a separation (internal) in the tire, debris on the hub flange, or even a bad wheel bearing.

Find a shop with a Hunter Road Force machine and ask for a full road force balance.