2021.5 CX-9 Vibration at Highway Speeds

I’m having the same issue on our 22 cx9 signature. I think it’s making our little guy sick or cranky in the car cause he seems completely fine in our other car with the same car seat. Does the rear axle replacement solve the issue? Or is it something else. Been to 2 different dealers and the 2nd one was more inclined to try and fix. There were 2 other cX9s with the same issue present that mazda keeps seeming as normal….
 
I’m having the same issue on our 22 cx9 signature. I think it’s making our little guy sick or cranky in the car cause he seems completely fine in our other car with the same car seat. Does the rear axle replacement solve the issue? Or is it something else. Been to 2 different dealers and the 2nd one was more inclined to try and fix. There were 2 other cX9s with the same issue present that mazda keeps seeming as normal….
Hey, my issues with vibrations were solved after the dealer changed both rear CV shafts. A couple things to note, I have xice 3 winter tires mounted on new rims that also experienced the same issues as the summer wheels. I also had both sets of wheels balanced on the hunter road force, which is a better machine than the typical/ normal wheel balancing machine-- tough to locate a shop with it with an operator that knows how to use it well.

Interested to see your results.

The replacement of the rear CV shafts on the cx9 was suggested by someone else on these forums, which I used to sell my case. I can't take credit for this fix but based on my own experiences I can confirm this resolved my problems 100%.

Kid doesn't get sick back there anymore 🤷🏾‍♂️🥳🙏🏽
 
It's the tires. I have the same issue with my 2021.5 CX-9 Kuro since new. Also noticed the vibrations on the first highway drive, in the steering wheel, and seats to a lesser degree. Currently at 1200 km. The car drives extremely well except in the 100-120 km/h range. Unfortunately, both OEM tire choices are preety poor for this car. I have the Bridgestone Ecopias. One look at Tire Rack reviews will show that Falkens and Ecopias are dead last in their respective category. Thinking back to my test drives on the 2021 Kuro and GT trims (with Ecopias), both test cars had vibrations to a certain degree on the highway. I believe the issue is more prevalent on this car with 20" rims and that some individuals may not be susceptible to vibrations as much. I certainly will not be able to accept the highway driving as is, until the problem is completely fixed. My dealer mentioned that this was the first time they have run into this problem on a CX-9 as well.

The first dealer visit was at 500 km. They acknowledged the vibrations and performed conventional balancing of all 4 tires, and found that the front two tires were out of balance from factory. The ride felt slightly better for the remainder of that day. Next day, same problem. It seems that tires are flat spotting when the car is sitting overnight. Second dealer visit was at 1000 km (yes I drove a lot in the first week of ownership). The dealer performed an alignment (slight correction to front left), took all 4 tires off the rims, rotated tires 180 degrees on each rim, and performed conventional balancing. They confirmed that the vibrations were less noticeable, but not completely gone. They will proceed to perform road force balancing at another dealer early next week, since they don't have the machine in-house. I drove the car on the highway this afternoon, and the vibrations were almost unnoticeable. Eager to see what the situation will be like tomorrow. If the road force balancing doesn't work, the dealer will request a new set of tires and rims from Mazda Canada. I'm not pleased with these problems on a new vehicle, but the dealer has been very supportive and they confirmed that they will solve the issue.

In another CX-9 vibration thread on the forum, one of the users was able to solve the issue permanently by switching to Michelin Premier LTX tires. I will report my findings early next week.
Did you ever get your vibrations issues resolved?
 
So I'm still scheduled to replace the CV shafts later this month but wanted to provide an update on something else. Before doing the rear CV shafts I wanted to be damn sure it's not the stock tires/rims (falkens on 20's)... As they're known to be of crud quality.

I had a tire shop change my tires to the Michelin x-ice tires on steel rims (18inch) and also asked them to roadforce the winter set-- which they did.

Problem with vibrations still there. Visor, phone on the magnet, all seats, front mirror etc vibrates still in the same way. It's to the point where my six year old often vomits in the car from getting car sick (doesn't happen on our other older car that doesn't vibrate).
We've had this car since brand new and on top our oil changes (Pennzoil platinum) and all other maintenance at the dealer.

So now that by process of elimination I've ruled out the Falken tires, hopefully it's fixed with the rear CV shafts. If this is the case, Mazda ought to recall this and not give consumers the run around for years and force the community to come together in this way. Shouldn't expect this in a flagship.

Other than this, I do like the car very much... But this issue is enough for me to leave the company. Even if they put a loyalty credit in finance for returning customers on the table...

Will update you guys in two weeks or so.

🤞
Did the cv shafts get replaced? Did it help your vibration issues?
 
This issue could have easily been avoided if Mazda still allowed us to buy the FWD only CX-9! Better mileage too…

(spoken by someone who lives where it never snows)
 
Did the cv shafts get replaced? Did it help your vibration issues?
Yup, I posted a fulsome update, possibly in another thread. Coles notes is, replacing both my rear CV's 100% fixed the vibration issues I was having. A few other CX9 owners reported this fix for them as well. I can't take the credit as someone else (smike?) suggested it I think... but demand this be done under warranty!
 
Back