I took my 2018 CX-9 Signature to Discount Tire this morning to have a tire repaired. The tires are original Falkens and came with it when I bought it used this year. Had about 16,000 miles on it.

They found that the tire I pointed out had a patch but not a plug installed, as did another tire. A third tire had a nail in the sidewall so the only way I was driving out was if I replaced the one tire with a nail in the sidewall. Unfortunately they didn't have the Falkens in stock and I was told that because the CX-9 is AWD the transfer case was at risk by mismatching tires.

This matches what I looked up: "Replacing just one or two tires on an AWD vehicle could cause unnecessary wear and tear on your drivetrain, or confuse the traction control system to think that you are frequently losing traction. ... The same is true for mismatched tires."

Anywho, they did have the Yokohama YK740 GTX in stock in the size I needed (255/50 R20).

So I just bit the bullet and bought them. The ride is definitely quieter and smoother.

I have 30 days to decide if I want to switch to a different tire. I was hoping to get the Michelin Defender as that tire has 10k more mileage warranty.

 

I think the difference in outside diameter with mis-matched tires is the problem for AWD.

 

Check out TireRack for reviews of your new tires to see how they will likely be I the long run.

I have had Yokohama tires in the past and was extremely happy. All models are not the same so check them out. They could be great.