I hate vehicles.
Not that this is a repair forum but what is it doing?
No power starting from a stop. Takes like 60 seconds to get up to 50km/h. Without getting too exciting here, it has a background of electrical problems. We have a pretty great transmission shop near where I’m located, so hopefully another kick at the can and they can solve it, because it’s out of my league to fix myself at this point.
Are you starting out in second gear? Almost sounds like it’s in limp-home mode, like there is an electrical fault with your transmission and it’s stuck in second gear as a safety. Either that or engine misfire/clogged catalysts, engines have a lot of ways to run poorly, but transmissions generally don’t have a reason to drag the vehicle down and still shift properly. Can you feel it upshift multiple times to 50mph?
You’re a smart cookie. It is in limp home mode, according to the transmission folks, caused by some sort of electrical malfunction.
The truck is a Frankenstein, and a lot of stuff that was mixed and matched caused electrical issues. It has an engine in it that isn’t the original make or model.
I never took it to 50mph, only 50km/h, as I didn’t want to highway drive it. It didn’t feel like it shifted once between 0 and 50km/h.