Coolant leaking

I have a 1988 gmc sierra with 145,000 miles. When driving in town coolant is leaking slowly out the exhaust manifold. When on the freeway, going over 1,000 miles, it doesn't leak. At the same time we lose oil at a quart per 300 miles around town but only half a quart or less per 1, ooo miles on the freeway. Aroung town when stopped at an intersection for a light when we step on the gas to start up we leave a huge cloud of blue smoke. Could both problems be a bad exhaust gasket, manifold gasket?