Symptoms
Temperature climbing on hills, when towing or at idle with the A/C on; coolant smell; a low-coolant warning on the EVIC.
The fix, step by step
- OffroadXtreme lists an insufficient cooling system among the ZJ's common problems.
- Pressure-test the system and check the radiator for blocked fins and leaking tanks.
- Replace the thermostat, check the fan clutch (or the electric fan on a 5.9) and replace old hoses.
- Then fill with the correct coolant and bleed out the air.
- ExtremeTerrain lists 12 quarts for the 4.0 and 14.9 for the V8s.
Tools & part numbers
- Cooling-system pressure tester
- drain pan
- hose-clamp pliers
- funnel
Where to buy the parts
Omix 17101.46 radiator, ZJ 4.0Quadratec ↗Amazon ↗
Cold Case aluminum performance radiator, ZJQuadratec ↗Amazon ↗
Mopar 52028186AC thermostat (TJ/XJ/WJ/ZJ)Quadratec ↗Amazon ↗
Cooling system parts for 1993–1998 Grand Cherokee ZJQuadratec ↗Amazon ↗
Hunting a used or discontinued part? Search eBay Motors for Jeep Grand Cherokee ZJ parts →
Rated for a competent home mechanic with a decent tool kit. Confirm torque figures, fluids and procedures against the factory service manual for your VIN, support the truck on stands rather than a jack, and work at your own risk (disclaimer). Some parts links are affiliate links, which pay us a small commission at no cost to you.