vibration on new tires

[190E26FTW]

Originally Posted By: Joe1
I recently replaced the OEM Yokohama 205/50/17 tires with Bridgestone Ecopias in the same size at Costco. The vehicle is a 2015 lmpreza.
At highway speeds above 60mph, l notice a wobble type of vibration. It is similar to a situation l had last winter where snow and ice buildup on one of the wheels caused excessive vibrations and wobbling. Removing the snow fixed that issue. The OEM tires never had this issue otherwise.
Will having the tires rebalanced fix this? Is it possible that one or more tires are defective? The Costco location l took it to is only a year old and has brand new equipment.
I plan on taking it back to Costco later this week, but wanted to get some feedback here on how to proceed.


Take it back to Costco but tell them to recalibrate their machine with the full calibration one and not the quick one. Their machines are used so much they are off. I had the same trouble as you using high end Bridgestone tires. Same thing with shaking violently at highway speeds. They tried to blame my car being old and old shocks and this and that. I said take a look...those Bilsteins look old? Control arms and springs are all new too . So dont let them bully and blame your car. Bridgestone quality has been so so esp for heavy cars like Mercedes. It even affected our light Honda Accord.

We switched to Michelin Premiers now and its been super smooth and quiet. Great rain tires also. Costco should take care of you. Ask for a new set of tires, but if I was you I would go with Michelin and swap over. Most likely its not your car since you didnt experience this shaking before. I ve only had 1 bad set of Michelins and that was the MXV4 bought from Tires Plus. They blamed my car and this and that. Called Michelin and they told me to take it to Discount Tires/Americas Tire with a claim number in order for them to Road Force check them. They did it and yup...all 4 were defective due to run out. So I got a new set of Michelin Pilots for my troubles no extra charge. So now I only buy from Americas Tire or Costco.

Talk to the Costco tire manager and then go up from there to store manager. Most likely you dont have to go that far.

 

[ChrisW]

At my work we have the Hunter Roadforce Elite and it does wonders on being able to detect assemblies that are out of round. That is, if the operator knows how to properly use the machine's abilities (our machine does not have the straigh-track feature).

I have found that through personal experience on my own mazda6 and a set of Pirelli PZero All Season plus (245/45R18 100Y) that how much runout an assembly has is greatly affected by how well the beads of the tires are seated to the wheels. On a couple of my assemblies, roadforce was cut in half by simply remounting the tire using extra paste on both bead seats of the wheel. All my assemblies measured 15# or less with my lowest at 2#.

In your case a vibration at or around the 50mph range would be in the first harmonic, 70 is second harmonic and 90 the third (very loose interpretation from reading the manual for the Hunter RFE) sounds like a balance issue to me (although if they're truly balanced then I would think it's excessive roadforce, anything over 21# would be a lot to me for a tire that size and likely the vehicle that uses that size). Can't say that I've spun many bridgestone tires that had excessive roadforce numbers. If Costco' balance machines have 'smart weight' ask them to balance it with smart weight off but you may have to get the tires roadforce measured and matched.