Re: temp gauge moving
Recommend you perform:
1. Cooling system pressure test.
2. Radiator cap pressure test (or just replace it for <$10) if it is old. Mine started to go at 60K miles (3 years). Stant is a decent replacement brand.
Ensure that the overflow recovery tank level is in-between the HI-LO marks with 50% HOAT coolant after your pressure test(s). Then, monitor the level for a couple of days to see how it varies. Check at the same point each time (like before the first start in the morning). As air pockets bleed off the cooling system, the recovery tank level will go down. Replenish the recovery tank and eventually, the level should stabilize.
Hope this helps.
'08 WK Limited, 5.7L HEMI, Quadra-Trac II, Bright Silver Metallic, Class IV Hitch, Michelin LTX M/S tires, Billet Technology oil catch can, Fumoto oil drain valve.