XJs are forgiving vehicles, but a bad purchase can turn into a money pit fast. Whether you're buying your first XJ or your fifth, this checklist covers what to look for before you hand over cash. Take it with you. Use it.
This is the big one. XJs rust from underneath. The floor pans, rocker panels, and frame rails are the areas that can make or break a purchase. Get under the vehicle. Press on the floor pans from below, soft spots or holes are disqualifying unless you're prepared for a full floor pan replacement. Check the frame rails along the full length, and look especially at the rear corners where the unibody meets the hatch area.
Surface rust on undercoating is normal and generally cosmetic. Through-rust on structural metal is a different story.
The 4.0L inline-six is a great engine, but head gaskets are a known weakness, particularly on higher-mileage examples. Symptoms: white smoke from the exhaust when warmed up, coolant loss without visible leaks, milky oil on the dipstick, or overheating. Pull the oil cap and look for a white creamy residue. It shouldn't be there.
Ask when the coolant was last changed. Old, acidic coolant accelerates head gasket failure. A seller who doesn't know when the coolant was last changed is telling you something.
XJs have a reputation for running hot. The cooling system design is fine when properly maintained, but neglect here compounds fast. Look for dried coolant residue (white or rust-colored deposits) around the radiator cap, hose connections, and the overflow tank. Squeeze the hoses, they should be firm, not mushy or cracked. Check the radiator for bent fins and corrosion.
Ask if the thermostat has been replaced. A stuck thermostat is a common cause of overheating on XJs and is a cheap fix, but it tells you what kind of maintenance history you're looking at.
Park on flat ground and cycle through all gears. The AW4 automatic transmission (on most 4.0L models from 1987 onward) is generally reliable. Watch for slipping, hard shifts, or clunking. Check the fluid, it should be red and not smell burnt.
Engage 4WD. On the NP231 transfer case, shift into 4Hi and 4Lo and confirm both engage cleanly. Listen for grinding or hesitation. Grinding when shifting to 4Lo is a warning sign.
Pull the differential covers if you can (or ask when they were last drained). Dark, metallic-smelling gear oil that hasn't been changed is a red flag on a vehicle that may have been used off-road hard. Gear oil is cheap. Rebuilding axles is not.
The XJ's unibody is its structural backbone. Look for separation, cracking, or rust along the seams on the inner fenders, firewall, and along the rocker panels. These areas take stress, especially if the vehicle has been lifted or driven hard off-road. Separation at seams is repairable but costly, factor it in.
A lifted XJ is not automatically a problem, but a badly lifted XJ is. Ask what lift is installed and who did it. Look for signs of professional installation: clean welds on any custom brackets, matching parts, no improvised hardware. Check the CV axle angles if it's a lift over 2 inches, excessive angle kills CVs fast.
Take it on the highway. Get above 50 mph and hit a bump or change in pavement. Death wobble, a violent shimmy in the front end, is common on lifted XJs with worn track bars, ball joints, or tie rod ends. If the steering wheel shakes violently, the vehicle needs front end work. This can range from a track bar upgrade to a full front end rebuild.
XJs leak. All of them, eventually. Common sources: valve cover gasket, rear main seal, front crankshaft seal, and oil pan gasket. Look at the ground where it's been parked. Look at the bottom of the engine from below. Some seepage is part of life with an older vehicle. Active dripping should be priced into any offer.
Test every window, every lock, the cruise control, the dash lighting, and the AC if equipped. The XJ's electrical system is simple and fixable, but diagnosing gremlins takes time. Know what's working before you buy. Non-functional power windows are common and fixable, budget accordingly.
Look at the carpet seams at the floor pan junctions. If there's rust breaking through the floor under the carpet, you'll see discoloration, soft spots, or actual holes. The headliner condition tells you how well the vehicle was stored, a sagging, water-stained headliner suggests water intrusion from the roof seams or sunroof.
Ask for any maintenance records. You won't always get them, but sellers who have records usually volunteer them. A seller who knows when the timing chain (on 2.5L four-cylinders) or head gasket was done, when the axle fluid was last changed, and what spark plugs are in it, that seller took care of their XJ. No records aren't a dealbreaker, but they're information.
A solid XJ under $5,000 is still findable. A clean, rust-free XJ from the Southwest commands a premium for good reason. Know what you're getting into, price for the work needed, and don't let enthusiasm override inspection. The right XJ is out there, find one that won't fight you from day one.
