I posted this here because I tend to appreciate the more considered opinions here than other similarly themed forums. Some interesting posts.
I haven't figured out the character of the Colorado forum yet, and that's where I initially read about the AEV conversion finish issue. I heard back on the other forum about it though, and that specific truck was super early in production (first dozen produced according to the owner, who is a GM employee), and the owner of a later production vehicle checked his and it's been remedied (it's not the prettiest work, but it's under other body work, so not really a major issue as long as it does the job). So that's a big relief.
To some degree, the lower quality of materials (thinking specifically dash pads and that sort of thing) is part of being a truck. For $50K, if I wanted a BMW, I'd have several to choose from. It's a tool first. I thought the headliner in the Colorado left some to be desired, for instance, but the headliner in the Gladiator doesn't actually exist... I was too disappointed in the Toyota to look up, so I don't know how that turned out there. It's the scratches and such that get to me in a brand new car.
Back to the topic, I have spent far too much time over the past few months researching the current mid-size offerings. I am currently deployed overseas so I won’t be able to get a new ride until January at the earliest. My research has led me to settle on the same three trucks as the OP, being the Tacoma, Colorado ZR2/Bison, and Gladiator Rubicon (I think the Ranger is hideous and am not considering it). Having ridden in a Tacoma and read reviews/complaints online, it sits in a very distant third for me as it would honestly be almost a downgrade from my current 4Runner. That Colorado seems like a good fit, I like the idea of the MPG/range of the diesel and have driven a few of the global midsize diesel trucks over here in the sandbox during the past few months and found them adequate. I have also driven a number of new Chevy Silverados here. My big issue with the Colorado is the aforementioned Chevy build quality and the cheap looking/feeling interior that I have become well acquainted with over the past few months. With the Gladiator, I absolutely love the way it looks (looks are subjective, I know, I just like boxy looking vehicles) and the interior seems very nice to me. I would likely end up with the V6 as the diesel, though I’m fine waiting for it to be released, is unproven and the last version wasn’t exactly renowned for its reliability. The price is high, though research has shown a multitude of people being able to price for around 5% off invoice (8-10% off MSRP) by going through different dealers and special ordering their truck (which, again, takes extra time but I have time).
In the end, I would probably be happy with either vehicle. If I was able to get the aforementioned discounts on the Jeep it would bring it to more within 5 grand of the ZR2, which I think is fair given the extra safety features and much nicer interior. In the end I’ll just have to test drive to get a feel for them, perhaps the IFS vs SFA front suspensions will make a difference, only time will tell.
TL;DR: I agree on the build quality of the Chevy, the engine/transmission of the Toyota, and the price of the Gladiator (though this can perhaps be reduced if you shop around). I’m eager to see which way you end up going as perhaps it will help my own decision making process.
I may have to look a little harder for deals on the Jeep. I'm in Denver, and it's like part of the initiation is buying a Subaru or a Jeep depending on your altitude. The Jeep salesman disagreed with my characterization that "it's full MSRP or go pound sand", but then went on to say that there no way they're coming a dime off MSRP...
The car engine in a truck is, IMHO the big downside of just about any midsize. I don't like V6es at all from an engineering perspective, and would take... I can't think of a configuration I
wouldn't prefer to a V6... My current truck is the final leg of my tour of the Big 3, and it's a 2004 Dakota with the 4.7L. I liked the Mercedes V8 it's based on, and it's the closest to an appropriate engine in the class. I used to exclusively do classic cars, but a bad wreck and a kid on the way has pushed me into the modern era, or I'd stick with the old school rolling stock. I have an M1009 in the barn I need to do something with...
I definitely looked into the Ford. Not at all impressed. My Dakota is about to eat its second set of head gaskets due to poor design, but I'd take another Dodge over a Ford. Multiple bad experiences there. Less anecdotally though, I don't think they did a good job Americanizing it. Chevy went a little too far IMHO on the 2.8L, but Ford took it too far in an entirely different direction while simultaneously seeming to forget to do anything at all. The rear seat configuration is what sticks in my craw mostly. I use the back of my truck constantly to carry things, and the rear seat setup in the Ranger is the most halfassed thing since... I don't know... I feel like when trucks first started having back seats they still put more effort into them than that. The drivetrain is the real deal killer. A solid I4 is preferable in a small truck to a V6, but that is a highly strung little thing with what has to be an incredibly busy transmission. I think that engine debuted in the base Mustang? Not a truck application. Not a truck engine. Beyond that, I find it so odd, but not odd at all at the same time, that Ford brought what is essentially a 10(?) year old platform back to the states as their re-entry into the midsize market. It's a very poor effort that can only be described as rushed and half baked, and it shows. They're supposed to completely redo the platform in two years (I think that's what I heard most recently), and it's hard to imagine the cost analysis that went into federalizing a platform like that in lieu of expediting development of a new platform. That extra year in such a booming section of the market must be expensive. Then again, Ford's recent rushed development exploits (the dual clutch in the passenger cars) didn't exactly go well...
As for the EcoDiesel's issues, it's a VM Motori (Fiat owned) design. The 2.8 Duramax was initially designed by the same firm, but the design was bought a decade or so ago, and started independent development at GM. It's sort of an evolutionary offshoot with an extra degree of removal. There are definitely some things I don't like about the current Chrysler engine (the single use fuel lines come immediately to mind), but don't yet know if GM is guilty of the same poor decisions. I'm trying to get in contact with a tech at the dealership to get an idea for what's going on there.