I have the Colorado and the HD, and have had two 1500 Z’s…but I traded the last 1500 on the 2500 z
the Colorado is the most “complete” off-road setup of the three in my humble opinion. I don’t have the bison nor would I get that package if I bought another Colorado - it simply doesn’t need it and the additional weight for the motor is a negative. The size is just right for off-road fun, hunting, and going damn near anywhere while being able to still haul dogs, gear, guns, etc (within reason, it’s not four guys to elk camp pulling a sxs…that’s what the HD is for
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). It “looks” the part too, vs the 1500 I always felt kind of blends in a bit (that’s also a good thing too). After three rear main seals, it’s been great for 4k miles or so.
What I miss from the 1500 - I really enjoyed the 3.0 diesel in the 1500, in 25,000 miles it was flawless for me, smooth powertrain, had solid fuel mileage. I appreciated the 1500 cab size, space, and additional bed storage. Suspension was butter smooth (maybe a bit too soft at times) - the bed was easily accessible and the overall truck size was extremely manageable in any setting. Colorado is getting a few MPG better than the 6.2 so the overall range isn’t much better here, probably a wash.
What I won’t miss - the 6.2 was certainly fun for a bit, the small tank and atrocious mileage was a deal breaker for me. combined with the potential for lifter or whatever engine issues, I traded for a 3.0 at 14k miles as I felt like I could deal with a DEF sensor now and again vs getting a new motor. The 3.0 drank DEF pulling / under load for me, normal driving it used very little.
Colorado nor the 3.0 will win a stop light to stoplight shootout with a teenager. that simply wasn’t why I bought either, i would buy something else entirely if thst were my objective
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Ultimately, I wanted daily drivability and something that excels for off grid hunting and farm use. Either are very good IMO, the HD is for the heavy lifting tasks.
Your mileage may vary, I’m not looking for a debate here, just giving my personal experiences and thoughts.