I'll try to make this as short as possible. This is a rear ac truck. Ac Was never right in this truck in the 10 years I've had it.. cooled but not very well. Compressor started to come apart. Shrapnel in lines. Everything is new execpt front evap. Including lines. Evap was flushed thoroughlyVacuum pulled for 4 hrs held for about 20. Charged 3.9 lbs. It was 85 degrees the day I finished it. Low side 45-50 high side 275ish 56 degree air at idle. Drove it for 30 min was very happy with results would hit 52 on the highway. Next day was 98 outside took it for a drive. Air wouldn't get any colder than 68 on highway. Hooked up gauges .low side 80 high side hit 475 before I shut it down. New fan clutch and a furnace fan blowing on it 75/420. 68 degree air.. high side will drop to 350 if I turn rear air off. Any advice would be great!