I'm headed to the daks on Aug 21-22. We are planning on arriving at the Loj around noon on Saturday and camping at Marcy Dam.

On a non-holiday weekend should we have any trouble getting parked at the Loj and finding camping at the Dam? We will bring tents, so it's OK if the lean-to's fill up.

We are planning on hitting Trap Dike that afternoon, then either Marcy or the Algonquin loop on Sunday. So, we could camp at Avalanche, but I'd much rather drop our gear sooner and go light and fast.

The lean-to and camping area for the Trap Dike and Avalnche Lake is further in than Marcy dam, it is before the steep part of the trail.
I am not sure that camping near Avalanche Lake is allowed...
Either if you camp at Marcy Dam or further in be aware that those areas are highly frequented by black bears...I met one of them camping there one night...
Parking should not be a problem at the Loj.

Have fun

Holiday weekend or not, the Marcy Dam LT's are quite popular due to 1) their location, 2) their proximity to the TH and 3) the easy terrain of the Van Hoevenberg Expressway. Good thing you're bringing tents, as I would bet the LT's would be full by Saturday afternoon.

If you're thinking of hitting Marcy on Sunday, I'd suggest camping at the LT's at either Lake Colden or the Flowed Lands. Although it would make for a longer "fully-loaded" hike, both of these are closer to Trap Dike than Marcy Dam and are much closer to Mt. Marcy for Day 2.

Should you be leaning toward Algonquin, however, Marcy Dam might make more sense. The trail from Lake Colden up to the Algonquin/Boundary col is steep, and you might not want to hike it fully-loaded (assuming you'd be doing Algonquinand then out to the Loj).

Don't forget your $7 for parking. Or is it $9 now...?

I was up there last weekend. Parking was 20 for 2 nights, but with my adk membership card, it was 10. FYI

OK, so it might be crowded, but we won't get turned away from parking at the Loj or tenting at the Dam. Good enough.

I've always avoided this area because of the crowds, but it's probably high-time I checked it out.

I took a crew of inexperienced but fit guys (5 total) from Basin to UWJ this spring, based out of the upper Bushnell lean-to. They loved the scrambling, but hated carrying packs of their cheap, heavy car-camping gear. It was over 10 miles total to the lean-to and back to the car, which was a tough weekend for them. So, this time I'm humping all the common gear and we'll camp near the trailhead so they can go packless on the Dike and whatever else we do. I think they will enjoy themselves much more that way. Otherwise I'd camp further in, for sure.

try camp avalanche that may be a good alternative up from mary dam, may want to arive earlier then noon if you plan to climb the trap dike and enjoy it,