98 grand cherokee laredo is making a knocking noise dont know what it is, maybe a head gasket? cost?
When I pulled into my driveway this morning, my engine started making a knocking noise. tThe oil pressur was very low (way below the add line). I added 2 quarts of oil and it is now in the safe zone. I started the engine, and it is still making the noise. My Aunt says it may be a "blown head" and my dad says it may be about to "throw a rod". What is it? How hard would it be to fix? How much should it cost?