I find the "known problems" list rather indicative of the design problems inherent in the Trailblazer platform.
How many unit bearing hubs must one replace?
I'm lifted, and my OEM ones are fine at 107k miles
How many thermostats (with a complete housing that is almost impossible to reach)?
My factory one was fine when I replaced it at 100k miles when I changed the coolant, belts, hoses, plugs, wires, and all the other crap that you're supposed to replace at 100k
How many electro-mechanical fan cooling fan units?
Mine is fine at 107k. The later ones use the original design. The bean counters made the engineers change the clutch to a cheaper design for the early ones. Even still, this nearly always lasted past warranty
How many rusted through transmission lines?
salt issue, not cold. Having said that, mine are still shiny
How many rear axle bearings and seals?
I know you did them on yours, but that's not common at all
How many stepper motors?
common on early ones. Maybe the only cold (and hot) weather issue on your list
How many ignition switches?
Not very common at all
Anyone hear any excess wind noise?
not a cold weather issue
What about rack and pinion seals?
Not at all common, but not a cold issue
Anyone have spongey brakes?
Not very common, but not a cold issue
I'm sure that no one has had to deal with the cam actuator...
These don't last forever, but not a cold issue
Clogged cats are never an issue, right?
This is a potential issue with anything of any brand with modern, 3-stage cats. Not a cold weather issue
U-joints just come out of an aluminum driveshaft with ease, ah ha...
Wear part. Low failure rate. Not cold weather issue
Anyone experience a rusted out fuel pump or fuel filler neck?
Rust issue, salt issue, not a cold issue. Happens on steel. Sorry.
Surely someone out there has experienced an inability to shift the auto transmission due to plastic parts failing...
I've actually never heard of that, but if so, it's likely they were made brittle by running too hot, rather than anything cold related.
Add an extra ground wire from battery to engine?
Not a cold weather issue. Not even really an issue at all, but a performance mod for a little better performance.
Power steering cooler replacement anyone?
Not common, but if so, rust issue, not cold issue.
I'm just hitting the big issues that virtually every TB or derivative faces -- all design issues that start to show up a few years down the road -- and things that we all know exist with our platform.
Is the TB a lump? Of course not... Is it all that it could have been? Not even close. Are there bright spots in the design? Absolutely, with the engine leading the way! But run the differential axle shaft through the oil pan? Really?
I just find that cold weather makes virtually all of the above conditions worse by far and I've submitted my gripe. Just hoping my own TB makes it until the weekend so that I can add more new parts...