lower Intake manifold gasket replacement on 2002 GMC Safari

My van is losing coolant and I believe it is going into the motor oil. I do not see any outside leak. I was already told that it is going into the oil.

Asked by for the 2002 GMC Safari
Don't drive the van with contaminated oil. The coolant will destroy the bearings! We should pressure test the cooling system first but I would also want to make sure your headgaskets haven't failed. Vans are difficult to work on because of the location of the engine. Good luck and happy holidays.