Symptoms
Coolant smell, green crust or seepage at the upper tank seam, often around 100,000 miles, and creeping temperatures on the trail. OffroadXtreme notes that the 4.0 runs hot and recommends an all-aluminum radiator.
The fix, step by step
- With the engine cold, drain the coolant and remove the upper and lower hoses.
- On automatics, disconnect the transmission cooler lines and cap them.
- Unbolt the fan shroud and lift it back over the fan, then remove the radiator mounts and lift the radiator out.
- Transfer any brackets, fit the new radiator and shroud, reconnect everything, refill and bleed the air out with the heater on high.
- Buy the right radiator for your transmission: Griffin's ExactFit listed here is for manual-transmission Jeeps, and CSF's 3426 is specific to 2005–06.
Tools & part numbers
- Drain pan
- pliers for the hose clamps
- line wrench for the cooler lines
- funnel
- coolant to the spec on the cap and in the owner's manual.
Where to buy the parts
CSF 3426 radiator, 2005–06 TJQuadratec ↗Amazon ↗
Griffin 5-00032 ExactFit aluminum radiator, 1987–06 YJ/TJ/Unlimited (manual trans)Quadratec ↗Amazon ↗
Crown Automotive 52080183 replacement radiator, 1987–06 YJ/TJ/UnlimitedQuadratec ↗Amazon ↗
Fairchild MCH1064 upper radiator hose, TJ 4.0Quadratec ↗Amazon ↗
Hunting a used or discontinued part? Search eBay Motors for Jeep Wrangler Unlimited (LJ) 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.