Generally you should fill the coolant to the top by removing the radiator cap. Make sure the engine isn't hot before filling. Make sure you have some coolant in the coolant reservoir and it will finish sorting itself out.
I took off my upper radiator hose today planning on replacing the tstat, and when I put it back on, turned on the engine, it's just full of air. Is there any way to let the air out?
If the air isn't purging, that's a symptom. I suspect the radiator cap could be going bad. Should suck coolant (from the overflow tank) back in to the main system at cooldown via vacuum relief. I would start by replacing the radiator cap (Stant or good quality equivalent).
When you refill the coolant system, try to park pointing slightly uphill. Refill the radiator and let it perk down. Squeeze the top hose until the air bubbles appear in the filler neck and it will refill the upper hose somewhat. Repeat several times until no more bubbles appear. Top up the radiator and overflow tank. Finally, make sure the overflow tank is at the high mark with coolant solution.
Run engine until t-stat opens and you should see more bubbles appear at the fill neck. Refill again to take up the air space. There is a bleed plug over the t-stat housing, but I did not have to use it when I changed coolant. All of the air came out with the above approach.
Check your coolant overflow tank several times over the next week and refill as necessary (as the air burps out of the coolant system).
BTW: Think the '05's use HOAT coolant like the '08's. MOPAR recommends not mixing anti-freeze types.
HEMI CLUB MEMBER #45; SILVER WK CLUB MEMBER #13
'08 WK GC Limited. 5.7L HEMI. Quadra-Trac II. Bright Silver Metallic. Class IV hitch.
Michelin LTX M/S tires. Fumoto oil drain valve. Billet Technology oil catch can.
The 3.7 and 4.7 have a bleeder plug at the upper hose inlet. With a stone cold engine, completely remove it (you'll need an allen key), fill the system until fluid starts coming out of that hole, replace the plug (again with the allen key), and then fill the overflow tank until it's full. Don't touch the bleeder plug again.
Start up the Jeep and let it run with the heater on full heat. After you reach the middle of the temp gauge, shut down, let the vehicle cool off, and add whatever makeup fluid you need. Repeat this part of the process two more times. Have a beer. Air should be gone and fluid level should be stable.
2006 WK Laredo 4x4 4.7L
1993 ZJ Laredo 4x4 4.0L — Dead, sold, and rolling again