I had something very similar. Stock 20 hankooks. Dealer balanced and rebalanced, checked alignment. Dealer would do something say it’s fixed I would take the truck away and vibration was still there.
Anyway after doing this 3 times they replaced all 4 tires under warranty. Smooth as butter since.
22 PB here. If the roads have snow the trunk is in 4A or 4H mode and normal driving mode.
Never experienced that rear end lock up, also no bed ballast.
I find even towing a Seadoo in normal mode with a PB messes up the transmission after unhooking the Seadoo, the shift points are all off and not smooth.
I prefer using towing mode for anything towing, and when you go back to normal mode with nothing in tow everything is still smooth.
The Service dept is not concerned with keeping your truck up to date. Unless you have a problem or TSB, or recall that ties to an update they won't do it. If you have a really good relationship with your service dept they make hook you up as a goodwill gesture.
The over the air update process...
I have a 22 PB with the stock 20" hankooks. I also have a set of winters for it. Wanted to get rid of the snow setup and hankooks and go to a 3PMSF setup.
Like for like sizing would be the MICHELIN® DEFENDER® LTX® M/S 2 275/60R20/XL 116H
Would the 285 fit stock?
MICHELIN® DEFENDER® LTX® M/S 2...