Naw, that isn't how they work.
If one is slipping, it'll burn to the ground in less than a mile.
Neutral oil is the same as park oil.
Only varible pressure in any automatic is 'secondary' and downstream of the older style governor or the newer style step motor to overcome spring resistance of any given shift valve.
Everything else is one static, constant line pressure except reverse oil which is multiplied by 2.5 because of the gear reduction involved.
Like the other fellas say, change the filter and the oil.