Toyota Repair: 98 Toyota Corolla pulse-vibration at high speed, wheel bearings, toyota corolla


Question
HI.  I have a 1998 Corolla that is in good mechanical condition.  All service is up-to-date and I had a new transmission put in it in Jauary of this year.   It has 103k miles.  

A few days ago, I got the tires rotated and balanced and the oil changed.  Now, when I am driving and get up to about 60mph, it starts to vibrate, but it is not a constant vibration.  It lasts for about 1 1/2 second and comes in 1/2 second intervals.  There is some vibration that is constant in the car which will not go away no matter what I do.  Balancing, Alignment, nothing gets rid of this minor vibration and it is not a nuisance.  However, this "new" jolting vibration is not the same.  

I can't recall whether this was happening before I got the oil changed and tires rotated and balanced because I only drive the car around town and to work.  But, as soon as I got it changed, I left to go out of town.  

I have ruled out the wheel bearings, loose lug nuts, cv axel, and don't know what else to check.

Also, I should note that I do not feel any loss of power when the vibration occurs and The car seems to run fine otherwise.  

Thank you.

Answer
Did this vibration start after the tires were balanced and rotated or was that a repair attempt to fix the problem and it didn't help?
I realize that you are saying you can't recall if this was the case but it's important for me to know this, in the meantime try having the tires put back to where they were and see if the vibration goes away and let me know.