Regardless of size, a tire's handling and durability is directly tied to using the appropriate inflation pressure for the vehicle. With a variety of wheel and tire choices for new vehicles, it's essential to rely on the vehicle manufacturer to specify the appropriate inflation pressure for the tires. Using the vehicle's weight capacity for each axle and other considerations, the manufacturer can best calculate the psi needed to ensure the tire handles and performs well.All too often, many drivers and mechanics assume the maximum tire pressure listed on the tire's sidewall is what is recommended for proper inflation. However, that number represents the maximum pressure that's safely allowed, but is likely higher than what is recommended by the vehicle manufacturer. Tire pressure can vary on several things, including:Changes in temperature Changes in altitude TimeFor best results, look for a placard on the inside of the driver's door or a similar chart in the owner's manual to determine the recommended psi for your application.
I had a lot going on this past weekend, and found myself crisscrossing L.A. and Orange counties in our 2014 Jeep Cherokee Limited. Saturday morning's chosen road was particularly pleasant and I was really enjoying myself until... ...the Tire Pressure Monitoring System (TPMS) warning light started blinking. The pressure display screen automatically popped up on the driver display screen, but it showed all four tire pressures to be bang-on the specified pressure of 33 psi. I pulled over and confirmed this with a quick check, but as I was doing it I knew it wasn't necessary. A blinking light, you see, means a problem with the system itself, not the tire pressure. A steady light means you have a low tire. This distinction is coded in the TPMS regulations and noted in the owner's manual. So I made a mental note and went about my business. The blinking warning persisted for about a minute or two. After that it went solid as if to say, "You've seen my alert. Now I'm going to back it down a notch so you don't get annoyed with me and trot out the electrical tape."
My errand-filled day resulted in many stops, and this pattern repeated at every restart in order to make sure the driver (me) didn't forget to have it checked out. The warning light would blink, the tire pressure display screen would override whatever was on the display screen, and after a minute or so the blinking light would downgrade to always-on status. At one point I was paging through the driver information screen and found a "Service TPMS system" alert on the Stored Messages screen. Why wasn't this screen the one that automatically popped up? If it's a fault with the system itself then there's little point in conjuring up the tire pressure display. Why leave the discovery of this clarifying service message to chance? For no apparent reason it all went back to normal several key-starts and some dozens of miles later. No more blinky light at restart, the tire pressure screen retreated to its usual background position and the Stored Messages screen cleared itself. It's as if I dreamt the whole thing.
I'm not exactly sure, but I have a couple of guesses. The central brain could have missed a few reports from one of the wheel-mounted tire sensors. A low sensor battery might do it, but they're supposed to be good for 10 years. Maybe I drove through a region of high electromagnetic interference. I don't recall any mysterious radio towers along my route, though. And the nearest military installation is dozens of miles away. Besides, the pressure screen that popped up always displayed numbers that made sense. And as I drove they changed up and down one or two psi in response to heat, sun load and driving enthusiasm, as per usual. Whatever it was, the fact that it took time to reset itself makes sense. The system would have to see a string of uninterrupted successful transmissions to rebuild "confidence" in the data and extinguish the light. The same thing happens with some systems when you install a new wheel sensor with an unfamiliar serial number. Such systems can "learn" that an unfamiliar sensor "belongs" after enough successful and persistent transmissions are received.
Still, we're going to keep an eye on it and have it checked out at the next service visit. Before that I may drive back to the same spot to see if some sort of weird local interference is to blame. Dan Edmunds, Director of Vehicle Testing @ 6,616 miles See 2014 Jeep Cherokee Inventory in Your Area Build and Price Your Car Used TMV from $13,719A machine like the 2014 Wrangler Rubicon X takes commitment. If you're going to buy one of these suckers, do yourself a favor: Thank the kindly salesman for his help, peel the scratch-prone, byzantine soft-top's side and rear panels off the truck and light them on fire right there in the front of god and everybody. You don't need those panels any more than you need pavement, and brother, with this thing, you don't need pavement.Jeep calls the Rubicon X the most off-road oriented model the company has ever produced. With its electronic locking differentials, sway bar disconnect, and crazy low 4:1 transfer case, the base Rubicon is no slouch.
The X adds in legitimate armor in the form of steel rock sliders and off road bumpers.RELATED: To go off-road solo, you need these 8 toolsJeep noticed that most guys were taking a sawzall to the plastic end caps on their Rubicons to make room for bigger tires, so engineers made the steel caps on the Rubicon X removable. Undo the bolts, and you have an unmatched approach angle. Of course you do. There's space behind the bumper, complete with a built in access panel.Engineers opted for no-bullshit 255/75/R17 BFGoodrich KM2 tires. They're soft enough to scramble up just about any surface, and those big lugs and deep voids make slogging through mud and sand a nonevent. RELATED: Jeep: The Adventure Never StopsThat's all good stuff, but the Rubicon X also carries along some decidedly less hardcore accoutrements. For starters, those wicked tires are wrapped around painted 17-inch aluminum wheels. Get frisky in a rock scramble and you'll find yourself with a nasty collection of scratches and gouges in the soft metal.
Give me a set of steelies to match the hardcore rubber and I'd be a happier boy. There are heated leather seats indoors, too. While the hides clean easily enough, they feel out of place on a rig that's built to go bashing through the wilderness.Jeep has built more than a million JK-generation Wranglers, and people still stare when you come bombing through downtown. It's hard to blame them. There's always some beauty to be found in utility, and the Rubicon wasn't not molded by wind tunnels or corporate groupthink. It was hammered into shape by rock trails and sandy scrambles.When you're up to your nostrils in email, there's nothing better than seeing this sucker sulking in the driveway. I blew off the office, threw some necessities behind the back seat and headed for Windrock OHV to spend some time in the hills.I can't say enough about how much the Pentastar 3.6-liter V6 has done for the Wrangler. There's 285 horsepower and 260 lb-ft of torque at your disposal, and with 4:10 gears, the Rubicon feels good and quick.
It'll rock and roll down the interstate at 80 mph as comfortable as can be with plenty in reserve for passing. RELATED: The next Jeep Wrangler might be aluminumIt still sounds like a Grand Caravan, but nobody's perfect. What it lacks in lungs it makes up for in fuel economy. I saw an average of 20.1 mpg over the course of my week with the rig. If that sounds bad, you never suffered under the boot heel of the old, unquenchable 4.0-liter straight six, or worse, the 3.8-liter V6.On the road, the Wrangler feels like an old school truck in the best way possible. The soft coil spring suspension and solid axles float and wiggle, and there's plenty of body roll at every corner. Crossovers have conditioned us to think every machine should drive like a Camry; The Rubicon reminds me that it's good not everything does.There's no better time to hit an off-road park than in the middle of a dreary week. The trails are abandoned. I poke my way up Trail 22 from the general store. The trail map marks this one as a moderate, and it's nothing a Subaru Forester couldn't contend with until about halfway through.
Out of curiosity, I leave the beefy KM tires aired up to 35 psi as I work the truck through shallow streams and around the tall poplar trees that grow here.Each time I approach an obstacle I see as problematic, the Rubicon makes an easy show of it. Large boulders, deep crevasses in the clay, and slick mud hills are made easy with grip and lockers. RELATED: The 2014 Ram Power Wagon is the Jeep pickup we asked forThe trail ends with a ragged rock bald, and for the first time all day, I'm not certain I want to keep going. With no spotter and those shiny aluminum wheels, I'm terrified I'll cause some serious damage. I get out, eye the rocks, and pick my line. Back in the truck, I drop the transfer case into four low, lock both axles and disconnect the sway bar. Doing so gives the front axle the articulation it needs to pick its way over the stair steps with all the drama of pulling into a mall parking lot.The short 95.4-inch wheelbase means the Wrangler never once drags its belly as it works its way up the two-foot steps.
I quickly realize that like the Porsche 911 and Corvette Stingray, this machine is far more capable than I am behind its wheel.From 22 I work my way up and down the technical switchbacks of 42 and 49. Some of the bends are so tight I have to three point the turn. While the Rubicon X comes with a six-speed manual transmission as standard equipment, this tester was saddled with a five-speed automatic. The transmission is the only thing on the truck that feels dated. The gearbox got hung in neutral in the transition from drive to reverse more than once, making for some hilarious near misses with rocks and roots in the middle of close quarters maneuvering. RELATED: Photos: 2014 Easter Jeep Safari at MoabI stop for lunch in view of the big windmills that sit along the ridgeline here. Each blade is longer than a semi trailer, but at this distance, they look small enough to pick up and put in my hip pocket. There's nothing but wild mountain slopes and a snaking web of trail between here and there.
I don't feel any breeze, but the big blades spin on anyway.As I wind closer to pavement, the path gets tighter and tighter. It's amazing how small your world can get when you're worried about punching a rock through the driver's door, but this is exactly what the Rubicon was engineered to do. There's a reason folk around here call these Jeep trails. They're wide enough for Chrysler's darling off-roader and nothing else.I pop out on a wider gravel trail, and it falls off the mountain in a swift decline. Before long, I'm back on the main highway just outside of Oliver Springs.At $34,595 (base MSRP), the Wrangler Rubicon X is a rare specialty tool in a world that scarcely needs it, but I'm glad it exists all the same. A light drizzle starts down out of the sky on the ride home. With the side panels back at the house and the glass windows down, I smell the rain and feel the temperature fall long before I see the first drops on the windshield. It's a perfect moment. I put my arm out the window just to feel the rain on my skin.