that long of a trailer, with the shorter wheelbase of the Tahoe, you really need a good WDH with built-in sway control, not a cheap one with a friction anti-sway bar.
the Equal-i-zer or the Reese Dual-Cam would be the minimum. a ProPride or Hensley would be the best but they are very pricey.
you can get an Equal-i-zer shipped to your door, for around $450 from RVW.
do you have a brake controller or did you not research that either?
that's required by law and may have contributed to your white knuckle experience by not having any trailer brakes.
you can get a Prodigy BC from RVW also, starting under $100.