Yes. If your Jeep's heater core is leaking, coolant vapor gets pumped through the vents along with cabin air, and it settles on the glass as a thin, oily, sometimes sticky film that's harder to clean off than normal window fog.
The heater core sits behind your dashboard and works like a small radiator, using hot coolant to warm the air that blows out of your vents. When it develops a crack or a failed seam, coolant doesn't just leak onto the floor; it can also vaporize and get blown directly into the cabin every time the heater or defroster runs. That vapor drifts toward the windshield, the coolest surface nearby, and condenses there as a greasy layer rather than evaporating as normal moisture would.
A few details can help you tell this apart from ordinary window haze, which usually comes from dashboard materials releasing vapors over time in the heat. A heater core film tends to feel oilier to the touch, often carries a faint sweet smell, and comes back noticeably fast, even right after you've wiped the glass clean. You might also notice the floor on the passenger side feels damp or smells sweet, since coolant can drip down into the dash and onto the carpet during the same failure.
This is one of those problems that's easy to dismiss as just needing a better glass cleaner, but a leaking heater core means your Jeep is both losing coolant and blowing it into the space where you and your passengers are breathing. It's also a sign your cooling system has one less place holding fluid than it should, which can affect how well your engine manages heat over time.
If your windshield keeps fogging up with a film that wipes away and comes right back, it's worth having the heater core checked rather than replacing wiper blades or trying every glass cleaner on the shelf. Hoover Street Auto Repair in Ann Arbor can pressure test your Jeep's cooling system and confirm whether the heater core is the source before recommending a repair.