Coolant pressure cap.
The first thing I would try is to replace the coolant pressure cap. For years my 2006 LBZ would not stay full of coolant until I replaced the pressure cap. Since I replaced the cap three years ago it has not lost another drop of coolant. It is an inexpensive item that is often overlooked by mechanics.
One of Jim's old DP articles addresses the pressure cap issue and that is what lead me to change my cap.
Good luck
John
*2006 Chevy, 3500, 4X4, DRW, (LBZ) D/A, CC, LT, 252K Miles, 19.5" Wheels, Mag Hytec Transmission Pan and Differential Cover, SS Grill Guard, Racor 2 micron aux fuel filter, 100 Gallon Aux Fuel Tank, using Edge Evolution, Predator Diablosport, Kennedy ECM tune, Fitch Fuel Catalyst.
*2006 Four Winds, Dutchman, 36', RV, D/A, 5500 Kodiak.
*1993 Harley Davidson, Turbo charged, Springer Softail.
*2007 Pontiac Solstice.
*2005 Jeep, Liberty, CRD (diesel).
*Full-timing in USA, see America first.
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