No, the 2012 Colorado(4wd) has a torsion bar front suspension, will the 2013 silverado(1500 4wd) has a strut front suspension.
There is no air in line Fuel pump pressursizes line and air automatically bleeds from the injector Not enough fuel or pressure will cause rough start
Check all vacuum lines
It sound like your catalic convertor is stopped up. Unbolt it and drive it. If it runs a lot better, replace it or leave it off.
If you know the spark plugs and wires are good, then check for a vacuum leak. The vehicle is 11 years old, and you may very well have a crack in a vacuum hose. A leaking intake manifold gasket will also cause rough idle.
What might cause your 2002 Silverado 4.8 to run rough under a load could be clogged fuel injectors or a clogged fuel filter. It might also run rough under a load because of a transmission sensor issue.
Rough Country - 1927 was released on: USA: 23 October 1927
There could be several reasons that your 1995 Chevrolet pickup truck, will not accelerate and idles rough. The most common reason is a plugged fuel line.
Check the motor mounts.
replace timing chain