2021.5 CX-9 Vibration at Highway Speeds

I had a similar problem with one of the shock absorbers after it lost all fluid. It was fine driving at low speeds but it was more obvious when I hit a bump on the road. At highway speeds between 80-100km/h, vibrations were annoying until higher speed reached.

Damn you were riding on a spring eh. Must have been bouncing all over the place with a blown strut lol!
 
UPDATE:

Dropped the car off this morning to get the driveshafts replaced. Dealer sent me home in another Mazda 3 :ROFLMAO:

Service manager called me about an hour ago to notify me that they have fixed the problem. Will be picking up the car tomorrow around noon. Will let you guys know if that was actually the problem.

It's Monday now - will be back on Wednesday with results!
 
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Mazda CX-9 Grand Touring 2016
It's good that they found and fixed the problem. Driveshafts need to be in balance. Also, there is the small possibility of a manufacturing defect in the driveshaft or the universal joints at its ends.
 
UPDATE:

Driveshafts did not fix the vibration issue. However, the vibration is a bit different now - kinda feels front end.

Anyway, was only on the highway for 10 min this morning. Need more time to feel it out.
I am in contact with the service manager via email, I am surprised he is really trying to get to the bottom of this issue and is not trying to push me off.

Will be back with further updates.
 
SOLVED:

I can confirm 100% replacing the 2 rear CV driveshafts fixed the vibration issue. I no longer have speed specific vibrations on the highway! Best of luck to all others with vibration issues - I hope this information is useful in your resolution.

It is difficult to isolate the problem to the rear driveshafts as the car goes into limp mode with the rear shafts removed due to a speed sensor linked to the rear diff. My dealership bit the bullet, took the chance, and replaced the rear CV driveshafts as a last ditch effort and it paid off.
 
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Mazda CX-9 Grand Touring 2016
You may have had one defective CV joint. Replacing both saved the time and trouble of guessing which one was bad, although perhaps the bad one ran warmer than the other? Anyway, give your dealership's general manager thanks for the service manager who kept digging until they found your problem.
 

Fawiek

Member
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2018 CX-9 GT
SOLVED:

I can confirm 100% replacing the 2 rear CV driveshafts fixed the vibration issue. I no longer have speed specific vibrations on the highway! Best of luck to all others with vibration issues - I hope this information is useful in your resolution.

It is difficult to isolate the problem to the rear driveshafts as the car goes into limp mode with the rear shafts removed due to a speed sensor linked to the rear diff. My dealership bit the bullet, took the chance, and replaced the rear CV driveshafts as a last ditch effort and it paid off.
Glad to hear! I called up my service manager and he's willing to replace under warranty as well based on reporting these vibrations early on and being on top of my service schedule. Will update on my results after its done as well..
 
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2018 GT
Wow, glad you found the issue and I wonder if that was my issue as well. I may be getting back into a 9 in the near future so really glad you found the issue as the car was sweet ride and miss it.
 

Fawiek

Member
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2018 CX-9 GT
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.

🤞
 
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Mazda CX-9 Grand Touring 2016
I know that Falken isn't a premium tire brand, but mine have been very good. I don't have a lot of mileage on them, actually the snows get more miles, but the Falkens run smooth with no vibration or traction problems.