The heater core sounds like it may need to be replaced or the system needs to be flushed again. You said the coolant was full correct?
2008 JK Rubicon
-255/80/17 BFG KM2s, 16/59 JKU springs, 2013 Rubi rims, RC stubby hybrid front bumper, XRC8 winch with synthetic line, RR evap skid, and more to come
1998 TJ Sahara Sold
-3.25" RC spring lift, Eagle alloys 125s, 33x12.5x15 Cooper STTs, XRC8 winch with stock bumper mount
1994 YJ SE Sold
-4" RC spring lift, 33x12.5x15 Firestone M/Ts, Eagle alloys 125, and a 4 cylinder to boot
1960 Willys Wagon
-Going to be restored and painted Omaha Orange
"I would rather wake up in the middle of nowhere than in any city on earth."
Male RN Jeep Club #1