Porsche built the original Cayenne to prove that an SUV could drive like a sports car on streets and highways, but also hit trails and rocky roads with all the performance of a pickup truck. I bought one last fall after driving my 1998 Mitsubishi Montero from California to Colorado, where the anemic 3.5-liter V6 and upright body struggled mightily chugging up steep grades at elevation.
Specifically, the 2006 Cayenne Turbo I bought needed to serve as a storm chaser during ski season and an off-roader for overlanding trips. The combination of 450 horsepower, air-lift suspension, and a true transfer case with low range and a locking center differential allows the comfy Porsche SUV to meet my needs, though I clearly required something a bit more rugged than the seller's Continental summer tires before seeing any slippery situations.
Luckily, Toyo Tires stepped in and shipped me a set of Open Country A/T III tires for a long-term review of how they perform on such a unique vehicle. Last month, I got good and stuck in knee-deep snow despite the Toyos' impressive capabilities in Utah up to that point. More recently, I finally took the Cayenne on a shakedown off-roading trip to test its capabilities—and the Toyos—in the sand, dirt, and rocks of the Mojave Desert.
Choosing A Perfect First Route
I joined MotorTrend Truck & Off-Road Group Content Director Sean Holman in a Ram TRX and AEM EV Director of Marketing and Public Relations Lawson Mollica in his 80-Series Toyota Land Cruiser for a quick trip northeast of Los Angeles. Both consider themselves experienced four-wheelers—as do I, though I drove the Montero or a Jeep Gladiator Rubicon on all my past trips. I warned Holman and Mollica that I needed something relatively tame for this first outing in the Cayenne, so they planned a route just off Highway 395 to explore the Bureau of Land Management's Grass Valley Wilderness Area.
Airing Down For Grass Valley
Somewhere 20 miles northeast from Edwards Air Force Base and southeast of Naval Air Weapons Station China Lake, we turned off the highway and aired down our tires. The Cayenne's trip computer and tire pressure monitors prefer somewhere between 40 and 50 PSI for on-road driving but I typically pump up to 50 all around to maximize MPGs during ski season. For this off-road excursion, I lowered to 30 PSI—not as low as possible but at least hoping to provide a bit more comfort and grip than at full pressure.
Spare Tire In The Trunk
Airing down also helps to prevent punctures and flats, an important consideration since my Toyos came in P-metric construction due to the Cayenne's 18-inch wheels. Installing the 265/60R18 tires at a scant 31 inches in diameter rendered my 29-inch factory spare useless, so I made sure to pack a full-sized wheel and Toyo in the trunk. And within the first five minutes off-road, I felt the reassuring presence of that tire in the back of my mind, since Homan pressed ahead full-speed in the TRX with all 702 horsepower vanishing in a cloud of dust. Mollica also pushed his Land Cruiser hard and I watched him catching air with the rear wheels over almost every whoop.
RAM TRX FTW
Holman and MotorTrend gave the TRX their Truck of the Year award in 2021—and it's easy to see why. With that supercharged Hellcat Hemi, long-travel suspension, and full-time four-wheel drive, the truck just gobbled up all the washboards and whoops we found. Holman likened driving it to riding on a marshmallow but he also aired down to 14 PSI before roaring off into the desert.
Figuring Out The Cayenne's Suspension Settings
As I brought up the rear, I played with the Cayenne's adjustable suspension settings. I first assumed that Comfort mode for the shocks would help to smooth out the dirt track's imperfections. But by about 20 minutes in, I landed on Sport for the shocks to go along with one level up for the airbags in the hopes of reducing deep dips and bottoming out. All of a sudden, I could almost keep up with Mollica and Holman charging along ahead, though my timidity at potentially breaking my Porsche on its first four-wheeling trip kept me at lower speeds throughout the day.
Looking back at photos from the day trip, I almost forget the wind storm that overtook the Mojave Desert for the entirety of our journey. A sandstorm even whited-out parts of the highway drive before we turned off the asphalt.
Creeping Coolant Temps Early On
But the wind also led to some paranoia for me, as we climbed up a long, easy grade from the pavement and the Cayenne's coolant temperature gauge starting creeping past vertical towards 200 to 210 degrees Fahrenheit. I bought this Cayenne knowing that one of the reasons that I depreciation helped me get such a good deal involves excessive heat in the engine bay—especially for Turbo models—that degrades plastic and electrical components quickly. Strangely, as soon as we stopped for a quick check-in, the coolant temp dropped to normal again.
Then, as soon as we started moving again, the temps started climbing. Weird. I even tried putting the transfer case in low range to help the engine rev higher and get the coolant and oil pumps flowing faster. No luck. When we finally turned a few degrees northward, the temps dropped and everything seemed fine from there on. I eventually concluded that having a hard tailwind prevented any air from flowing over the Cayenne's prodigious radiators, causing the coolant to circulate at the engine's operating temperature.
Build Choices Becoming Important
After about an hour of washboard roads and whoops, we came to a first little obstacle where a deep wash rutted across our trail. Holman went first in the TRX, taking his time to avoid snags due to the big truck's long wheelbase. Mollica went through more confidently, with a little extra ground clearance than a stock 80-Series thanks to his 33-inch tires and upgraded suspension. But his custom rear bumper holding a spare tire and gas can dragged a bit while pulling back up out of the wash—nothing terrible, just steel in the dirt and rocks.
Cayenne Notches A Victory
The Cayenne, meanwhile, took the little dip best. While waiting for Holman and Mollica to proceed, I lifted the air bags up to Spec Terrain and dropped the transfer case into low range with the center diff locked. Taking it slow and steady, I just crawled right down and then right up the other side, without any wheelspin or dragging. I think we could have managed even one position lower and in four-high.
Next, we drove up to a tight canyon section, where Holman needed to back up once just to ensure clearance for the long Ram pickup. Mollica and I, however, just moseyed right through no problem. But I did begin wondering how my future build plans, including a swing-out spare tire carrier, might affect the Cayenne's maneuverability later on.
Visiting Desert Memorials
Twice during the roughly 50-mile trip, we stopped to check out memorials set up in the middle of the Mojave. One commemorated an Air Force pilot who crashed his F-22 in the desert. The other included many rocks, plaques, and flags set up in honor of all the dirt-biking fanatics who lost their lives in pursuit of fun.
A portion of the trail even passed through a designated artillery range, so we made sure to stay right in the dirt road to avoid any unexploded ordinance. I found myself glad that Holman led up front using the online off-roading software onX—despite a ton of crisscrossing desert roads, he never made a wrong turn and we never needed to go in reverse.
Airing Back Up For The Cruise Home
After almost four hours, we ended up back at the highway and stopped to air our tires up. The Cayenne's onboard compressor performed perfectly, if slightly slower than the Viair that Mollica used to fill up his tires—which, in a funny twist of fate, were LT-metric versions of the same Open Country A/T IIIs that performed so well on the Cayenne throughout their off-roading debut. All in all, I came away impressed by the Cayenne's suspension and four-wheel-drive capabilities. That little concern about overheating evaporated when I chatted with Holman about what I witnessed and with all his experience, he immediately chalked up the little rise in coolant temp to the wind, as well.
The Grass Valley Wilderness landscape never required too much from our trucks or their drivers, to be fair. And though I felt the Montero might have been more fun simply because my concern levels would have been lower, the Cayenne probably delivered a slightly more comfortable ride. Next time around, I'll install the Eurowise skid plate currently waiting in my garage and try something a bit harder—in the meantime, the Cayenne cruised home at 90 miles per hour (while logging 20 MPGs) without breaking a sweat, a feat the Montero simply cannot match.
Sources: toyotires.com, blm.gov, aemev.com, and onxmaps.com.