So we are still waiting to confirm if a torque converter from a trailblazer would work and what would be needed? When you have shutter, that is representative of a torque converter issue right? I'm assuming price is the main reason to go with Trailblazer TQ over something aftermarket?
Well, I'm sure it would
work, as in "fit and operate". Yes, a failing torque converter can cause a shudder. Mine isn't shuddering, though. I have a shake that feels like an imbalance when I rev it in Park or Neutral to a specific RPM range. It may be there when driving at those same RPMs, but I can't tell due to road vibes. Because of how heavy the imbalance feels, I was questioning the crank pulley (which I'll replace when I pull the motor in a few months) and the torque converter since they are balanced when built and maybe a weight slung off.
If my stock converter is faulty, I could simply swap in a new stock one and press on. My mention of the Trailblazer converter is because it's a dirt cheap way to get a mildly higher stall speed which would result in a snappier take-off. But, it may be a bit too loose now that I've really looked into it. I'd have to get an aftermarket one specifically designed to be a little looser than my stock Tahoe converter but not as loose as the stock TB one. An aftermarket converter would be $500+, and I'm not in the market for a "performance" converter in the first place. What I really was questioning is if I have to replace it, would it be worth it to get a TB converter since it'll be the same cost, if not less?
Now that I've talked it over with you guys, I'm leaning more towards the crank pulley since it's the much more likely culprit. I'll disconnect the converter when I go to pull the motor and see if the vibes are still there. If so, then I'll know its the crank pulley. Hopefully, before then, I'll have someone that can hold the RPM at ~1700-1800 while I watch the pulley so I won't even have to test further.