Just trying to level it for now, unless I should just lift it half an inch and it will automatically adjust? I disconnected the battery with the truck in the air while swapping the starter and now my truck leans to the left. So I assume its not a good idea to disconnect the battery with all 4 wheels off the ground
I wouldn't worry about it. If the truck is off, you can do whatever you want. The system is static at that point. WHat you want to avoid is lifting truck by frame while the truck is running (unless you hit the AHC OFF button), otherwise the truck will think the angle is changing and attempt to adjust the suspension.
well the front driver side is lower than the right passenger
Caveat emptor, I'm not a Toyota engineer, I've just read the manual.
The problem with leveling is there are multiple states the system can exist in.
Post Height Adjustment State:
If you are on level ground and do a cycle from L to N, that will be what the truck thinks is level and all heights are set by the suspension via height sensors to make the truck zero out the height readings. If you are level at this point, then there is no reason to adjust anything (other than to lift). This may not mean your truck is going to generally ride level. Likewise, if it's not level at this point, that doesn't necessarily mean your truck doesn't ride level generally.
Post Driving State:
Once you start driving around, the normally closed gate valves between the axles are going to open at some point. This is going to balance the pressures between the sides of each axle. (ie. FL and FR and going to balance to have the same pressure on both sides, and same for rear). Now if you have a corner spring or anything else that causes one side to sit lower, no amount of adjusting AHC sensors/HOU is going to correct that. Only way to fix it is to make a change to the springs (spacers/shims/new springs) or fix whatever is causing the height difference.
With Techstream you can open the gate valves with the AHC utility. Possibly, the best course of action for most of us would be to get the truck on level ground, raise to N then open the gate valves with the utility. Then see where the truck sits. Decide if that's acceptable or if something needs correcting.
To me, the only reason to adjust the sensors, or to use HOU (essentially the same thing), is to get the sensors as close to reading 0 as possible when the truck is in the open gate valve state. That way there should be less random corrections while driving and at stop lights. Other than that it's not really worth chasing.
What would be interesting at this point is understanding how the yaw and acceleration/deceleration sensors play into decision the AHC ECU makes, when leveling and otherwise.