[Dr.Show-Me]

I drove a Colorado yesterday, and I'll tell you there is plenty of room for a smallblock and it would be an easy swap, other than emissions stuff. GM should offer it, but probably won't for at least a couple years. It would be ideal for the upcoming Trailblazer

 

[Dr.Show-Me]

GM isn't the only game in town. Although I prefer GM products, if they don't offer what I want, I'll buy from someone else.
I would buy a Trailblazer with a 5.3 or 4.3 tomorrow, but Jeep offers a similar product, and several others. GM has to earn my business, the question is will they?

 

[Dr.Show-Me]

You can buy a Trailblazer with a 4.2 tomorrow. That's pretty close.
Unfortunately, that model has been discontinued for five years. Sorry to break the news to you.

WOW, THANKS!!!! Who could have guessed that there were used Trailblazers out there! Thank you so much!

 

[Dr.Show-Me]

Will it be worth it? You're looking at a significant weight gain to get 50 or so more HP. Yes, the truck would feel quicker with the added torque but the 3.6 isn't lacking in power and is fairly well matched to the size of the Colorado.

It is likely that. A 5.3 would weigh barely more than a 3.6, with the weight being higher due to dohc heads, while the 5.3 is far. More compact and perhaps 50-75 pounds more. For the performance improvement and slight increase in weight, give me the V8 every time!!!