Tires using now- Bridgestone Turanza - 215/R65/16. I had same problem before replacing them but vibration was not as bad then. I have had these tires rotated at least 4 times over last 2 years. The vibration developed slowly to where it is now very noticeable. The vibration started somewhere around 2008. It is only noticeable at highway speeds starting around 60mph. I am in drive when it is noticed. Have never tried putting it in neutral while driving but will do that and answer this question later. It doesn't happen when braking and turning. It is felt through the floorboards, more so in back and front passenger side. It is felt in steering wheel but not as much as elsewhere.
I had a Firestone store tell me my vehicle calls for a transmission flush, not just a fluid change at 35,000 miles. So I had them flush it at 38,000 miles. Do I need another flush now or can I just get a change? Thanks.
I read the comments but there seems to be a variety of fixes. From tire balancing, to changing the tires, to replacing lower control arms, etc. The Quest engineer's comments said if vibrating all the time then needs balance. I have had a balance done 3 times but no fix. All tires are the same type bought at the same time. I called Nissan on the recall and they said according to my VIN #, my vehicle is not part of the recall. So what else could it be?