there are two problems, corroded steel and aluminum.together, yes aluminum will corrode and unfortunately forcing the bolts out without proper lubrication will damage the thread form in the aluminum alloy tube end.
Your best bet is like everyone said, penetrating oil of some type. Before applying the oil however you might try some heat, careful heat from a small torch or a halogen lamp to slowly soak in some heat .
Do this BEFORE you add the oil as the oil can pocket in cavities within and when heated create an expansive and explosive condition.
The heat , again careful heat, applied to the bolt will transfer heat to the aluminum the different metals will expand when hot and contract when cooled at different retes which may go a long way to breaking the corrosion at the thread joints and bolt shank. Then when fully cold apply the penetrating oil and let the oil work for at least a day.
If you can get you hands on an impact wrench perhaps at the local auto repair shop this will aid you greatly in breaking loose the corrosion also.
best of luck....remember heat first ..... penetrating oil later and do not over heat the aluminum.
mooseman
