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Like most automotive journalists, Iā€™ve been impressed with the capabilities of this latest generation of unibody SUVs (technically crossovers) and pickup trucks. They really are cost-effective, strong, and efficient. But my recent restoration of a full-frame 1988 F-150 pickup truck reminded me why todayā€™s body-on-frame vehicles will be driving decades after current unibodies are dust.

What is a frame swap?

Do you have a beloved full-frame truck, SUV, or pre-1960s car crippled by rust? You can always remove all the vehicleā€™s components from its current frame and have them bolted to a brand-new frame.

Jeep Wagoneer SUV's full-frame and drivetrain, painted for visibility.
2022 Jeep Wagoneer/Ram Truck frame | Stellantis

Will it be cheap? Heck no! RoadKill Customs warns that the process takes more labor than assembling a brand-new car. But it will give an old vehicle legs for another decade or more.

Because a frame swap is a possibility for valuable classics, we will see more full-frame trucks and SUVs on the road in the coming years. This includes current pickup trucks (except certain compacts), current truck-based SUVs, and many cars built before the 1960s. This does not include crossovers with ā€œunibodyā€ construction, even big third-row crossovers such as the Toyota Highlander. This also does not mean certain crossover-based compact trucks, such as the Honda Ridgeline and the Ford Maverick.

Can you save a body-on-frame truck or SUV?

A full frame swap is one of several options you have to save a full-frame truck or SUV. The vehicleā€™s construction also allows you to patch or brace its rusty frameā€”in states where this is legal.

A suspension bracket attached to the frame of a Ford F-150 pickup truck.
1988 Ford F-150 frame suspension brackets | Henry Cesari via MotorBiscuit

This summer, I began to swap the front-end suspension components on my 1988 F-150. But I found the truckā€™s traditional ladder frame rusted where the shocks and springs had been bolted to it.

Luckily, I was able to shape metal stiffeners to fit the blocky, ladder shaped-frame. Ā If my truck had been a unibody, stiffening it up would have been a complex feat of engineeringā€”if possible at all.

Can you save a rusty unibody?Ā 

A rusty unibody will be much harder to save than a body on frame. But humans are resourceful, and where there is a will, there is a way.

Henry Cesari standing next to his 1964 Dodge Dart car.
1964 Dodge Dart | Henry Cesari via MotorBiscuit

My first car was a 1964 Dodge Dart. It was a unibody dodge built before this technology was reliable. As a result, 1960s Dodge Darts and Plymouth Valiants are known for rusting out. Their load-bearing floor weakens and as the car bends in the middle, it becomes impossible to latch its doors.

My 1964 was just beginning to sag. To fix it, I had to get creative. Straightening the classic out required setting it on an alignment rack, stretching the worn unibody until it was aligned, and welding in frame-stiffener railsĀ  (imagine an aftermarket ladder frame). Luckily for me, Dodge had engineered frame stiffeners for the carā€™s convertible variant so there was a spot to attach the frame stiffeners to.

Any current unibodies that will someday be popular candidates for restoration will also someday have stiffening kits. Iā€™m thinking of vehicles such as current muscle cars or the Bronco Sport. But while future mechanics will develop tricks to save them, I expect the same mechanics will be much happier to see an old Toyota 4Runner, Jeep Wrangler, or truck because they know they can patch or swap the frame.