Drive line/tranny questions 2007 Tacoma

On my 2007 Tacoma with 4.0, 4x4 auto, I have begun to notice a slight roar sound at about 35-38 mph maybe coming from the tranny or drive line? (about 36,000 miles on truck.) It hasn't caused any problems but I'm wondering if I need to lube something that I haven't? It isn't the brakes as it does it without touching the brakes. I guess it could be tires but I'd be surprised if it stayed in this narrow range of mph.

On a separate issue, I'm getting a slight "clunk" sound when stopping at a stop sign. I think it is the slip yoke shaft in the drive line between the transfer case and tranny but there is no grease fitting on it. Any ideas?

A third issue. I notice when slowing for a stop sign, the tranny downshifts agressively decreasing the smooth "coast" that I'd get in the full-sized trucks I used to drive. Is this something others have noticed? Is there any way to change it?

I still love the truck. It is still the only truck I've ever had that made it through the warranty period without going back to the dealer.