I cannot believe what my eyes are seeing right now. This build by Nevada-based Jacob Collis involved cutting off the rear section of a first-gen Jeep Grand Cherokee’s roof and turning it into a pickup truck. But while hacking the roof off a unibody SUV is already a strange and questionable thing to do, the truck-ification of the Jeep isn’t the weird part — what’s weird is that Collis reinforced the unibody by welding on sail pillars from a first-gen Honda Ridgeline. Yes, you read that right.
We’ve seen so many strange build projects here on The Autopian that it really takes something special to get me bang on my keyboard, and this automotive Frankenstein, called by its maker the “Jenda GrandRidgeline Wagoneer,” absolutely qualifies, mostly because it makes absolutely no sense while at the same time making a tiny bit of sense. Hear me out.
A Jeep Grand Cherokee is a unibody vehicle, meaning that, instead of having a separate passenger-holding body bolted to a frame that handles the majority of the chassis loads, there’s just one single body designed to handle it all. Integrating the vehicle’s overall load-bearing structure into the body itself allows for more interior volume, better overall stiffness, weight-savings, and various other advantages. What it also does is make modifications to the body hugely problematic, whereas on a body-on-frame vehicle you could hack the body up all day and let the frame handle the loads.
For the longest time, pretty much all pickup trucks were body-on-frame only, since a roofless truck bed is hard to make stiff; sticking with a strong ladder under the bed to take up the loads just made sense. But then came the Honda Ridgeline, which eschewed the frame for a fully unibody design. How exactly did Honda build a frameless pickup truck that could handle the bending and torsion loads that a truck would see? Well, Honda engineers installed “sail pillars” to each side of the vehicle. That’s these:
If the concept looks familiar, it may be because the newly-released Tesla Cybertruck uses sail pillars to provide sufficient stiffness to handle road/towing loads:
These sail pillars (also called sail panels) are meant to tie the rear of the truck — where the loads come in via the trailer hitch and via the rear suspension — in with the roof, thus creating a larger moment of inertia to resist torsion and bending.
Maybe you can see where this is going. If cutting a unibody Jeep Grand Cherokee’s roof leads to structural concerns, and Honda fixed structural concerns on its unibody truck by incorporating sail pillars, then couldn’t one solve the Jeep’s problems by just installing the Honda’s sail pillars?
This is an absolutely outlandish thought. It doesn’t work like that! Those pillars have to be integrated into the original design, with Finite Element Analysis and all sorts of other simulations/tests done to make sure it all works together as a system, and it has to be welded into the structure just right. You can’t just stitch one truck’s sail pillars into a hacked up SUV and expect it to solve your bending/torsion problems!
Still, maybe it could help a little to tie that rear end together, and the idea of it is just so bafflingly absurd that I cannot help but absolutely love Collis’s build. “The idea originally came from this man out in New Zealand … the man who made [a pickup Jeep Grand Cherokee ZJ],” Collis told me over Facebook Messenger. “The problem is, if you look at this truck’s further photos you begin to see … where the piece on the back came from. It’s a fiberglass shell from a boat on the back, with a window panel placement and cutout,” he told me.
“When preparing the cut I took noticed of some of Jeep’s ZJ design features for an anti-taco [i.e. folding] effect. Should the B and C and D pillar ever wind up cut, they’re not compatible with a full fiberglass rear firewall,” he said. “The motor in these is usually a 5.2, and it has enough torque to twist and contort the body, even though it’s a unibody vehicle. And with the rear gone, I lost downward weight displacement in the rear because of the lack of a rear back.” I’m assuming he means that lack of a rear structure made the truck lose rigidity/strength needed to carry/haul loads or to go off-road.
“So to get the truck effect and give it some ability to retain its older safety feats, I gave it a full rear fire wall of an ’07 Honda ridgeline,” he continued.
I know it’s not the same thing as a Jeep, but frankly, I’d much rather have a stock first gen Honda Ridgeline instead, even if just 2WD. Still, I can empathize with the urges that owning a welder can feed. 😉
I guess he wasn’t finding a Jeep Comanche for the unibody, two-door, solid-axle 4×4 pickup Jeep he wanted.
I’m not understanding the need for sail panels to provide ‘strength’ on a unibody truck – here in Australia we have built unibody utes since the 50s without needing that sort of added reinforcement.
Early Valiant utes like mine were basically a wagon floorpan with a unibody ‘truck’ shape built upon it – and the chassis rails integrated into the floorpan didn’t even run the full length of the car – they had a big gap in the middle!
He custom built a v8 long wheelbase Amigo.
If you like some homemade Cherokee madness, you should definitely check out this youtube channel: https://www.youtube.com/@LowBuckGarage/videos
This guy recently turned Cherokee ZJ into funny car dragster by shortening rear of body and sticking front wheels half meter in front of the car!
He also has some other interesting stuff like: 1950s bus converted to RV, FC jeep turned to wild-west-style wagon, an off-road hot-rod – old style water-pumper dune buggy or WWII half truck wrecker and some more projects.
<insert:JeffGoldblum_could_should.gif>
This is awesome. Homebrew levels of execution, sure, but it’s clearly a labour of love. And you know what? I don’t think I’d like this idea better if it had been professionally coach-built. There’s just something more appealing to me about pulling this off in your garage without too much detailing. Great job! The Jenda “Dignus Mjolnir” Grand Ridgeline gets a solid 8/10 from me.
7/10 execution, but likely 9/10 from an engineering standpoint. And it does flow together well…with some additional thingies.
Wow. Um. Clean mod…?
> Dignus Mjolnir
He spelled Dingus Mjolnir wrong.
Also mjöllnir is old Norse, not Gaelic.
> I plan to do an XJ and give it to my wife and name it Minnie-Me …
> We’ve turned into family men now
Not for long
In all seriousness, though, props for having a vision and turning it into reality.
I think bondo would actually be stronger than some of those welds. Yikes.
Those look fine for unground body welds. Pretty hard to make a weak body weld, especially when factory cars are held together by questionable spot welds and bubblegum.
Spot welds are stronger than the metal around them–well, they are if they are good ones. A common test for spot weld quality is a pull test, where you try to pull the two pieces of metal apart from each other. The weld (commonly referred to as the “nugget”) should remain intact and the metal should tear around the weld, showing that the joint is stronger than the individual pieces of material itself.
There’s various forms of this test that put the joint in sheer, or a “peel” or any other specific thing that is feared could be a form of failure.
Well yeah good spot welds are good. Some factory spot welds are not that good, and factory arc welds are usually worse.
The Subaru Brat would like to have a word.
10/10 for the build, 0/10 for the taillight choice.
Ditto, but also the headlights.
Same, but also everything between the headlights and taillights.
..at least they weren’t tinted.
Whoever this guy is…he’s the kind of crazy that I admire.
wait I’ve seen this before…except it was a Fiero notchback becoming a fast back, and it wasn’t structural.
I think Mark Smith of Smyth Cars has created the best Grand Cherokee pickup truck design. And the cool thing is, it’s available for any aspiring builder to take on. In my eyes, it’s the next best thing to the original Comanche. https://www.smythkitcars.com/jeep-ute
I was thinking of this kit the entire time I read the article. In my perfect world though it’d be this build with Smyth’s fit and finish. Those sails work too well to ignore
Yep, was thinking Smyth the whole time as well. Am half-contemplating doing a Smyth Mk5 Jetta once the kid is done with the car.
David, I’m disappointed in you. First, you make it sound like the Honda Pilot was a pioneer in the concept of unibody trucks. Have you forgotten the legendary Jeep Comanche, brethren of the XJ? Secondly, you had the gall not to mention it at all in this entire article!
Finally, given the existence of the Comanche, I love how doubly insane this is. It has all of the insanity contained in the article, PLUS, to achieve a similar effect with much less effort and more success, it would probably work fine to swap over whatever ZJ bits you like onto a Comanche and add some cosmetic side panels.
Fair point. BUT, the MJ was a little more conventional in its design! It had a rear “frame,” which I suppose I could have mentioned, as i suppose he could have made his own?
The rear “frame” of the Comanchee is pretty much just some sheet metal on top of the same basic rails of the Cherokee, just like the old GM and Chrysler cutaway vans used to build motorhomes.
Well the Ford 1961-1963 F-Series “styleside” pickups were unibody. At least enough so that a big bump would render them inoperable. I think tha Falcon based Rancheros were more successful examples of unibody construction.
The “unibody” F-series are not unibody, they still have a full frame, the same frame as used on the step side and the later trucks that went back to a separate bed and cab.
Not unibody, called unibody because the cab and bed were unitized. They’re still body on frame, just not a two part body. Just like a Chevy Avalanche.