17-23*F in freezer isn't cutting it.....so food section will not get cooler
Do you have fans installed in rear outside compartment up near top?
Are the fans operating?
Is the fridge in a slide out?
Same lack of cooling whether on electric or propane?
There has to be good air flow across backside of fridge in order for it to cool properly.....pulled in thru bottom vent and out the top vent.
Your fridge is also 11-12 yrs. old.
Has this lack of cooling something new......or gradual?
If fridge has been operated while off level the cooling tubes could be clogging......off level operation causes improper vapor/fluid flow. This causes crystals to form and they build up blocking the fluid flow even more. Damage is accumulative....so the more times the fridge is operated off level the more clogging.