I have had new Yokohama avid gt put on 13 terrain (235/60/17, standard tires)...after one month, 4 balance and rotations ever other week it so, one road force balance...tires still bouncy and vibrate at certain speeds...including during some accelerations.

New rotors and all new pads on wheels, no other know front/rear end suspension issues.

Any ideas as to this possible issue?

If there was no problem prior to the tires, and the only thing changed was the tires, then it must be the tires. Bad tires. Have dealer replace them ... either discerner brand or same brand but different.

I recently went to “national chain” for tire rotation and balance and ended up with a vibration that they were unable to resolve inthree separate attempts including road force balancing.Finally the tech took me to the machine to show me that I had a bent rim; after I demonstrated a technique that proved that theory false, he then attempted to tell me I needed a new tire. When I told him that was fine, replace it, it’s got road hazard warranty thru company (in presence of manager) suddenly they discovered that the wheeel hadn’t been centered properly on the balancing machine. Rebalanced with no issues and has driven vibration free since. Moral ... you gotta stay on top of them.

I am thinking it’s the tire as well, although it could be the rim...unlikely it is that.

After a few rounds with Yokohama and the seller, they are putting my old tires back on...I guess I’ll need to get the same destination le that was on it originally...we’ll see after old ones put on it issue us still there.

Why are you changing the style of tire ? If your old tires do not vibrate when reinstalled obviously there is a physical issue with one or more of the yokohama avid gt tire or tires or the balancing done and, not a bent rim. If I liked the tires I would simply say try a different set of tires then.