The ‘Generals Highway’ Trap: Will Your Rental Rig Survive the Switchbacks to Sequoia?
Visalia holds a prestigious title: The Gateway to the Sequoias. For outdoor enthusiasts, the city is the perfect basecamp. You pick up your supplies, you fill your cooler, and you hitch up your trailer for the 45-minute climb into the land of the giants.
It sounds like a perfect American road trip. But for the unprepared driver towing a rental trailer, the road from Three Rivers to the Giant Forest Museum is not a dream; it is a mechanical nightmare.
The Generals Highway (Highway 198) is an engineering marvel, carved out of granite cliffs in the 1920s. It was designed for Ford Model Ts, not modern full-size pickups towing 30-foot campers. Before you hitch up and head for the Ash Mountain entrance, you need to understand the “Generals Highway Trap” and the physics of the 22-foot rule.
The Physics of the Switchback
The climb from the foothills to the Sequoia grove is relentless. You gain nearly 5,000 feet of elevation in just 16 miles. But the elevation isn’t the problem; the geometry is.
The road features over 130 curves, including several “hairpin” switchbacks that fold back on themselves at acute angles.
When you drive a car, your rear wheels follow a tighter arc than your front wheels. This is called “off-tracking.” When you add a trailer, that off-tracking is magnified. On a narrow, two-lane mountain road with no shoulders and a sheer drop-off on one side, this geometry becomes critical.
If your trailer is too long, you physically cannot make the turn without crossing the double yellow line into oncoming traffic. On a blind mountain corner, this is a recipe for a head-on collision.
The 22-Foot Advisory
Because of this danger, the National Park Service enforces a strict advisory: Vehicles longer than 22 feet are strongly advised against using the southern entrance (Hwy 198) to the Giant Forest.
This is the trap. Many renters assume “22 feet” refers to the trailer length. It does not. In many contexts of mountain driving physics, the concern is the combined length or the specific wheelbase. However, even if interpreting it loosely, a standard pickup truck is roughly 20 feet long. If you attach any substantial trailer to it, you are well over the geometry that the road can comfortably handle.
While you are not technically banned from entering (unless you exceed the commercial length limits), ignoring the advisory means you will likely find yourself stuck on a switchback, blocking traffic, with your engine overheating and your transmission screaming.
The Brake Fade Phenomenon
The climb is hard, but the descent is dangerous.
The most terrifying moment for a trailer renter in Sequoia National Park happens on the way down. After a weekend of camping, you head back toward Visalia. Gravity is now pulling your 5,000-pound load down a 6% grade for 16 miles straight.
Inexperienced towers ride their brakes. They press the pedal continuously to maintain a slow speed. Friction creates heat. On a long descent, the brake fluid can boil, leading to “brake fade.” Suddenly, the pedal goes to the floor, and the truck doesn’t stop.
This is why renting the right trailer is crucial. A heavy, dual-axle trailer without its own high-quality braking system (surge or electric) puts 100% of the stopping burden on your truck. A lighter, single-axle utility trailer is much easier to manage on these specific grades.
The “Northern Hack”: Highway 180
So, does this mean you can’t tow a trailer to the Sequoias? No. It just means you are using the wrong door.
Savvy locals know the “Northern Hack.” Instead of driving straight up Highway 198 from Visalia, they drive north to Fresno and enter the parks via Highway 180 (Kings Canyon).
Highway 180 is a wider, straighter, and more gradual road. It was built later and designed to handle larger vehicles. While it adds mileage to the trip, it subtracts stress. You can tow a larger rig into the Kings Canyon campgrounds (like Grant Grove) much more safely than you can wrestle it up the Ash Mountain switchbacks.
Conclusion
The mountains demand respect, and that respect starts with your equipment. The romantic image of hauling a massive camper up a winding road often clashes with the hard reality of physics.
For your next trip into the high country, audit your route before you rent. If you are committed to the southern entrance, keep your rig small, light, and agile. If you need the big toy hauler, take the long way around. By choosing trailer rentals in Visalia that match the road you are driving—not just the gear you are carrying—you ensure that the only thing breathtaking about your trip is the view of the trees, not the smell of your burning brakes.
