2007 with 50K miles has been at the shop for 3 weeks getting the power steering system replaced. Battery got a full charge last night, and truck got a hard restart this morning.

It starts fine, and Reverse is like normal. Put it into Drive with Foot on the brake, and all is well.

Take the foot off the brake and the suspension light goes off and truck lowers at once. You have to turn the truck off and then on again in order to get the suspension height back up.

Brake bulbs are both working fine, and none have been changed out.

Is this that brake light switch diagnosis, or something else?

 

I would put my money on it. Its an easy change. I had similar problems and when I switched out the brake switch problem was solved. You can also pry apart the old switch and you will probaly see black burnt residue everywhere.

 

The brake switch is a cheap and easy repair but may be worth getting fault codes pulled if that doesn't fix it. Throwing parts at the LR until you hit the jackpot gets expensive...