Monthly Update for September 2019 - 2018 Jeep Wrangler Long-Term Road Test

2018 Jeep Wrangler: Monthly Update for September 2019

by Dan Edmunds, Director, Vehicle Evaluation

September was another uneventful month for our Jeep Wrangler, although it racked up a few more miles than it managed in August. Most of the 1,229 miles we added were close to home. That tends to happen around here in summer when desert temperatures soar and the coastal breezes beckon.

Another thing that held back the mileage was the state of the tires. Not only are they starting to wear down to the wear bars, but two of them began leaking at almost exactly the same time and at the same rate. Because both front tires were low by the same amount, we first thought someone had misfilled them. But after filling them up again, they gradually leaked back down to the same point over the next several days, so we took the Jeep in to have them inspected and, hopefully, patched.

What Kind of Fuel Economy Did It Get?
No one ventured far outside Los Angeles this month, and it shows in the fuel economy. The month's best tank was only 16.4 mpg, which is very clearly below the Jeep's lifetime average. Some tanks were much worse than that, as low as 13.3 mpg while in the hands of one staffer with a particularly notorious commute. The result was a monthly average that came in at a paltry 15.2 mpg. That represented enough drag on the lifetime average to pull it down a tenth, from 17.7 to 17.6 mpg.

Average lifetime mpg: 17.6
EPA mpg rating: 20 combined (18 city/23 highway)
Best fill mpg: 24.6
Best range: 448.7 miles
Current odometer: 38,115 miles

2018 Jeep Wrangler

Maintenance and Upkeep

Flat tire(s) repair: $95 for three tire patches in two tires, plus remount and balance.

In an odd coincidence, the low tire pressure warning came on when both front tires were equally low. The pressures were so similar that we first assumed that someone had simply forgotten to air up after airing down for an off-road trip toward the end of last month.

But there was a problem with that theory: No one had aired down for an off-road trip in recent memory.

We aired them back up on the assumption that maybe they had been misfilled during last month's dealer visit somehow, but seven days later they were back at the same low pressure. It turned out both front tires were very slow leakers, and they were leaking at the same gradual rate. We eventually found a screw head in the driver's side front tire, but the source of the leak in the right front tire remained a mystery. We took it to Stokes Tire Pros for a look.

What Stokes found was interesting. The right front had not one, but two nails in it. Luckily for us, both nails and the screw were in the patchable middle region of the tread. They were able to install three patches, rebalance both wheels and send us on our way, but with a warning that these tires didn't have a lot of tread life left.

That much we knew, but we want to delay the purchase of new shoes a bit longer. The 40,000-mile milestone isn't far away, and we may want to toy around with a bigger wheel and tire package. There's no use buying new ones while that's still up in the air.

2018 Jeep Wrangler

Logbook Highlights

"Although the Wrangler isn't exactly a track star, it's surprisingly eager around town. The gearing is short enough off the line to make the familiar Pentastar V6 feel like it's gained a few ponies. I'm never caught flat-footed in this Jeep. When I want to get going or hit a hole in traffic, it's ready to rock. In today's world of slow-to-downshift transmissions and slow-to-spool-up turbos, the Wrangler's quick reflexes are a welcome throwback." — Josh Sadlier, director, content strategy

"I was heading south on I-5 this weekend and noticed once or twice the Jeep's hesitancy to downshift. I kept feeding in the gas pedal, expecting to feel a downshift and the additional acceleration that follows, but there was nothing. It wasn't until I added excessive pressure to the gas pedal that the shift finally arrived. Not sure if this is a fuel economy strategy or something else as it didn't happen frequently enough and I couldn't reproduce it. But it was strange nonetheless." — Carlos Lago, manager, feature content

"Though I've driven our Wrangler plenty, this weekend was the first time I heard the accessory fan at full song. It's so loud that it's like being in a passenger plane during takeoff! Fortunately, the fan shuts down pretty quickly, but I was surprised at just how loud it was." — Carlos Lago

"Funny Carlos should mention that because I've been thinking the same thing. Others have, too, and I'm actually subscribed to a Wrangler forum thread titled 'JL embarrassing loud fan' wherein this issue is discussed. What's going on can regularly happen at normal temperatures in the 70s or low 80s if the Jeep has been parked outside.

"When you start the vehicle, the A/C attempts to cool the hot cabin, and the main engine fan comes on strong almost immediately, trying to pull air through the condenser to speed the process. It quiets down as you start driving and speed picks up, at which point natural airflow takes over. But it is embarrassing when it happens right in your own neighborhood, and it can make you wonder if something is amiss. There isn't anything wrong, though. It's more a matter of the A/C system trying to cool the interior down quickly despite a cooling system that's compacted into the Jeep's slender nose." — Dan Edmunds, director, vehicle evaluation

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