My first post.

I have 2001 XJ with 4.0 liter engine. 90,000 miles. Drove it 600 miles to pick up a small trailer (1000lbs) without issue. On the way back, the heater stopped blowing hot air into the cab. Once home, I noticed that driving around town, the aux fan would come on around 210 degree and stay on. Coolant levels are fine. Any suggestions?

Gauge may be falsely indicating a little low. The ECU turns the efan on at 218F. Time for some cooling system maintenance....the hot months are almost here.

Djb knows his cooling system he'll get you fixed up fast. it could be time to start replacing tstats and other cooling sys maintenance

Thanks guys.

DJB: Should I start with the thermostat? Flush and fill? Water pump? Any direction would be appreciated.

First the cooling system seems to be working normally, But flush and fill and Tstat are never a bad idea. Also check the Mechanical fan clutch. As for the cabin heat, start looking for vaccum leaks, as that is vaccum controlled.

Here's my $0.02 worth. The entire cooling system can be replaced for +/-$250 in parts including a new rad. The XJ is simple to work on and with the old rad out, it's really easy to flush the head/block, install new water pump, t-stat and cover, fan clutch, hoses, belt, etc. If u replace everything at once, u only have to drain coolant once. U sleep better at night knowing it's all done.

I would go the DJB route. I just replaced my T stat and water pump. also i hear a high pitch sound when the heat is on. pretty sure its a vacuum line... ugh. anyways summer is the scariest time of the year for xj owners so if your jeep is new to you go ahead and replace everything. good luck

Although it seems senseless and expensive to start replacing parts sometimes but for sure every xj out there is a minimum of 10 yes old. What are the odds the previous owner took care of anything. A clean running xj will last you a long time

What seems senseless to me are the threads about brown lumpy coolant. LOL. Some parts/fluids are best replaced before they go bad/break/malfunction and i find replacing parts/fluids is done a lot easier on Saturday afternoon, in my driveway, when parts stores are open vs midnight, on the side of the road and nobody's open.

It's true weekends have become the relax with a drink and mess with my rig day. Whether it's a repair or just lubing an greasing it makes for a relaxing day

Peace of mind is relaxing also.

i would have to agree. Cold beer and a grease gun most weekends