95 Land Cruiser, air conditioner starts out cold, it has freon and then blows hot after the engine gets hot.
Find a good, independent shop.
No user serviceable parts inside.
I had the same problem with a 1990 Ford Aerostar. The problem turned out to be that the fan didn’t pull enough air through the radiator and condenser coils. The air movement was enough that the engine didn’t overheat, but as soon as the car had been driven a little bit, the air would blow hot. It turned out that the fan clutch was slipping and wouldn’t allow the fan to turn fast enough.’\
The mechanic diagnosed the problem by letting the car run with his gauges attached. When the air started to blow hot, the pressures shot way up. He put his shop fan in frot of the grille and directed air through the condenser. Immediately, the pressures fell to the normal range and the air became cool again.
I don’t know if your Land Cruiser has electric fans or a thermostatically contolled mechanical fan, but in any event, check for proper air flow through the radiator and condenser.
If it has electric fans, make sure the truck is warmed up, then have someone inside turn on the A/C while you watch the fans. If they’re not running, they should turn on. If they are, they should run faster.
If it has a mechanical (driven off the belt - which I think yours has), with the engine off, try and spin the fan by hand. It should turn, but with some resistance. If it spins freely, then your fan clutch will need to be replaced.
Make sure the fan shrouds are in place, and intact, too. If they aren’t, the airflow won’t be correct.