My 02 Grand Cherokee, 215,000 miles, has been losing antifreeze but I never see a leak, and its heat gauge shows running 210--220, Checked oil and no change in color or water in oil. In traffic it will heat up ,get moving an it drops down to 200.
Have you noticed the exhaust being a very thick white color? You could be burning the antifreeze. Your head gasket could have a pin hole in it. With 215k I wouldn't doubt it. Have you noticed the smell of antifreeze while driving? If you open the hood after driving when it's hot can you smell antifreeze? I just got rid of a Ford Ranger that I inherited because every time I would drive it, I could smell antifreeze. Never found a leak. Figured the head gasket was ready to go, so I put a for sale sign on it and sent it down the road. Didn't even have a 100k on it.
Could also be the intake manifold gasket or heater core leaking as well. HTH. -Jim
Search Jeep Grand Cherokee Questions
Are you a UK consumer? CarGurus now has a discussion forum in the UK.
Jeep Grand Cherokee Experts