We have a 40/60 pump currently, but we feel like the pressure is extremely low inside the house. I have not had a chance to check the air pressure in the tank yet, but that will be done this weekend. The pump works as expected, cuts in at 40 and out at 60, but the pump will only hold the pressure at 40 as long as water is being used, it will not build it back up until all water has been turned off in the house. Is there anything else I can check or adjust so we can have higher pressure inside? The tank is a 100psi tank. The whole system is less than a year old.
The problem you are describing is one of a lack of pump capacity. If when the water is being used in the house, the pressure cannot get past 40 PSI, it's because your pump is maxed out. If it USED TO work and has become worse, you may have a pump problem that should be looked at, i.e. sand infiltration, low water table, worn out impeller etc. etc.. If it has ALWAYS been like this, then your pump is too small, or rather too small to give you any more.
I have to agree with @J Raefield that the pump is maxed out. In my previous house I had a problem similar to yours. Just for information to compare, My well was 200' deep and had a 1/2 HP submersible pump. The maximum pump pressure was 64-65 psi. with the contacts on the pressure switch manually held on. When water was used the pressure fell to about 40 psi and remained there until the water usage stopped. This problem was solved by the installation of a 3/4 HP pump my 2 cents