It doesn't look like the Gabriels are available for the Avalanche. I was going to put on the yellow Bilsteins. A lot of people are reporting putting helper air springs on the Avalanches when towing. Since it needs new shocks anyway, figure I'll just try that first before adding anything else and go from there. There's not a great deal of tongue weight, and the back end of the truck doesn't lower much when putting the trailer on. Mainly, it's just shocks that you can tell are dead without a trailer. I might think about a bigger transmission cooler before next season, though. Or else just let it explode and put in a 5-speed.
Good point on the differential vent. I likely have submerged it, and it's about time to change the fluid anyway. I'll do that sometime after I've got my car back together.
I'll check out Overton's for a new cover.
I think we're going to stick to Brookville Lake at least for the rest of this season, and probably for next season, as well. Aside from being a nice location, the close aspect is a large part of what we're going for. It's one hour from truck starting to in the water, and that's most of the goal. Get to make some noise and go around, then park and just enjoy the water.