On my 2011 Subaru Outback, despite regular rotations, balancing, alignments and nitrogen, I had a vibration problem that the dealer diagnosed as badly cupped and unevenly worn tires -after only 30K miles. He recommended replacing the OEM tires with better tires, and, if that didn't help, that he could install (under warranty) a "Drivability Kit". He seemed to be deliberately vague about exactly what the kit was or did. Does anybody have an experience with the "Drivability Kit"? Is it to fix suspension design problems that cause excessive tire wear, or is it something that simply reduces the road feel? I'm wondering if it should go on before or after the new tires are installed, or if it has any value whatever. Any input would be appreciated.

I have never heard of a 'Drivability Kit'. If you can see for yourself that the tires are unevenly worn & badly cupped, you need to find out the reason why this happened. You could also go to a different Subaru Dealer and see what their diagnosis is and see what they recommend. You could ask them about the 'Drivability Kit'.

Assuming that you took your vehicle back to the car dealer, we're not surprised that the "problem" is everywhere but the actual vehicle. Based on your description, this is not a tire issue, but rather a problem with your Outback. There is no such thing as a "Drivability Kit;" why would there be if the vehicle is supposed to drive properly from the start?

Wow I've never heard of a Drivability Kit this must be something that the dealer or Subaru came up with. If they will install the kit under warranty at no charge to you I would have them install it before installing new tires. Take it out and test drive it and make your way to a local independent tire dealer and have them check your tires for replacement. I would also look at a different brand than came on the car. You said you rotate regularly so you should be on your sixth rotation. Cupping and irregular wear after only 30,000 miles is not normal. Most times this is caused by worn suspension parts (which you really shouldn't have) misalignment or worn shocks & struts. When you're shopping for tires at that independent tire dealer ask them if they could check your alignment when you purchase new tires. We start recommending shocks and struts after 50,000 miles and that is the industry standard for those parts to start failing.