Have you had a professional clean the coils? I had a similar problem even though I was vacuuming the coils regularly. After I had an experienced Subzero appliance person do it the problem went away. It turns out that there were areas that I wasn't able to reach to clean.

Thank you for responding. I haven’t had them professionally cleaned, but I’ve been cleaning them for 20+ years. The appliance repair person said they looked clean and determined the gasket was the problem.

It’s been over 2 hours and the temp is only down to 46 degrees.

In my 632, the door seals are kept warm by SZ routing the hot refrigerant lines inside the frame (opposite the seals). Normally one doesn't notice that the seals or frame are particularly warm. When my condenser coil fan started having trouble starting, the refrigerant started getting very hot, and it was obvious at the door that something was amiss. Under those conditions -- inadequate refrigerant cooling -- the refrigerator cannot easily reach its set temperature. If I left the cover off of the mechanical bay, even a badly operating fan was sufficient to allow the unit to work. However, replacing the fan was essential, and doing so fixed the issue.

I assume your tech checked refrigerant pressure or whatever to know that you don't have a leak. If so, then look at the fan and see if it seems to start OK and run at a reasonable speed. Also, with leather gloves for protection, if the fan is off then check it for excess friction. Observe fan duration. If it is on for a very long time then either the refrigeration system lacks efficiency or there is a heat leak into the refrigerator.

But in the past, when I‘ve done a deep clean, turning it off and such, it seems like it reached the target cold temp faster.

Well, when you turn it off to vacuum the compressor, the doors are probably closed, which keeps the inside cool, maybe 50° or thereabouts. And when you clean the shelves and drawers, you probably take them out and close the doors. But when you replace the seals, you have to leave the door open the whole time, so the inside reaches room temp., let’s say 72°. It takes longer to cool to 38° from 72° than it does from 50°. Does this sound like a reasonable explanation? How long was the unit without power with the door open?

It took about an hour to replace the gasket, the max temp got to 70. I left it alone all night and it did reach the right temp. I think I just had to be more patient. After it reached temp I put all the food back in from the ice chests.

I just posted another question in a new thread regarding the ideal temp.

“Observe fan duration”

What is the duration supposed to be?

I’m laying on the floor in front of the mechanicals (they‘re on the bottom). I can hear the fan. Should I time how long it runs? I never notice the sound when I‘m working in the kitchen unless I right next to the fridge or on the floor like now.

"What is the duration supposed to be?" By my comment I meant to imply that the unit was unlikely to be designed for a fan/compressor duty cycle greater than 10 to 20 percent if the door stays closed. Hence it might run for a half hour every four to six hours. I don't have a 601 to measure the actual value.

It came down to 38, but every time we open it for just a moment, it jumps up to 39 or 40. My giant family is now in bed, so nobody will be opening it til tomorrow.

The unit is reporting the internal air temperature that you just raised by opening the door. Get a thermometer with a extended wire probe -- for example ThermoWorks RT801 -- and plant the probe in a container of water in the refrigerator. Note stability of temperature.