Wanted to add a data point to this discussion, because in my case, the OEM Toyos are the not the cause of vibration. I bought my '17 GT used, with two newish Toyo A36s, and two that looked to be the original (judging by tread and data code.) I really had no issues with the ride; there was some noise and tire growl, especially from the more worn tires. But no noticeable vibration. It wasn't a plush ride, but it didn't bother me. I had an alignment done anyway after I bought it, figuring the previous owner probably ignored it, which is one way to wear out two tires well before the other two. (The other being to simply not rotate them, letting the drive wheels take most of the wear.)
I replaced the Toyos about a month ago, since I was getting close to the wear bars on two of them. Decided to try the Pirelli Scorpion AS Plus 3, in the 225/55R19. Tire Rack liked them on the Audi SUV they tested, and from their reviews, I was expecting a smooth riding, quiet, well-handling tire that would last well into the 70,000 mile warranty. Purchased and installed at Discount Tire, Hunter road-force balanced.
From the beginning, had a noticeable but slight judder around 40 mph, and a very noticeable and annoying vibration at highway speeds, i.e. 75mph +/-. Took them back and asked them to check the balance. This second time, they assured me they used the "sports car" setting on the Hunter machine this time. I never did get numbers, but I'm assuming the first time the machine was set in the mid 20 lbs. range, and the second time down in the low teens. They said they changed about 3/4 oz. on one of the rear tires.
Ride improved slightly. Could still feel a little bit at low speed, and the vibration was slightly diminished on the highway. Still very noticeable, some in the steering wheel, mostly in the seat. It had a pulsing, cyclic feel, and seemed to get worse with sideways g-force such as in a sweeping curve or when changing lanes. Also, the low-speed vibration seemed to be worse right when I left the house, before everything was warmed up.
In addition - because now I'm tuned in to feeling everything, every time I get behind the wheel - the ride seemed just on the edge of harsh. Every bump, crack, pebble, or expansion joint was transmitted to my hands or seat. That's outstanding in the Miata - I like being able to feel the crosswalk paint - but not so much in the near-luxury grocery hauler. But I would've gotten used to it, absent of the vibration at speed.
Took it back a third time. Explained I'm not too happy, still. Maybe the Scorpions aren't the right tire for such a light, small SUV? They're marketed as a light truck tire as well, so perhaps to get that strength and tread wear, they are too stiff for the CX-5? Dunno, but they balanced them once again - and THIS time, they found the front left needed another 2 oz. The ride was smoother on the trip home, but I never got over 45mph.
Couple days later, I made a 450 mile round trip, pulling a light utility trailer. (A drive I've done multiple times on the old Toyos, under the same conditions.) It was miserable. The vibration was still there, and the trailer made it resonate more strongly. Worst between 72-77 mph (I didn't attempt anything faster) but there even around 62-65 mph. Without the trailer, the vibration is improved over the last balancing attempt, but still there, and not something I want to experience for the next 70,000 miles.
The tires are coming off this morning - I'm still within the 30-day Satisfaction window with Discount Tire - and I'm having the Michelin Cross Climates installed. I always liked Michelin Defenders on my old truck, I'm very happy with the MXM4 run-flats on the wife's BMW, and I'm hoping Michelin's reputation for great ride continues with these.
Considered the Continental LX25s as well, and I know many have been very happy with them on the CX-5. They're not as universally loved across the board in online reviews like the Michelins are, and I'm not sure Discount Tire will let me get away with another 30 day test drive
. More importantly to me, the LX25 is marketed as a Crossover/SUV tire, while the Michelin is targeted at sedans and coupes as well as SUVs. After the Pirelli, I'm thinking I want something aiming more for sedan-like luxury, rather than truck-like utility.
Why didn't I choose Michelin initially? Good question. Probably because I live in the South and don't really need the additional snow/ice capability they provide; the treadwear warranty is less than the Pirelli, and they cost a little more. And there were nuances in TireRack's testing of these two tires that made the Pirelli seem a better fit for me. But driving is believing.
If these don't do the trick, then there's an issue somewhere else in the suspension that will have to be chased down. Or I'll just have to live with yet another Mazda having resonance-vibration issues (The NA Miata having a long history of "65mph shimmy" that I also experienced but managed to dial out with tire and suspension choices over the years.) I've got a little over 67k miles on the CX-5.
I'll post an update on the Michelins in a few days.