Which motor should we get.
We have decided to bit the bullet and get a new to us truck. We have a Chev with a 5.7 L and 220,000 miles. I am not against buying any of the big 3, Chev, Ford, Dodge. With that said, my last post...
Forum Discussion
Nvr2loud wrote:
I have the GM 5.3 with 3.42 gearing and 6-speed tranny. It pulls great, revs a little higher then my old 6.0 GM but that's okay.
If you choose the 5.3 there is an optional Active Fuel Management (AFM) that is known to cause engine problems over time. You can easily disable it with a low priced plug-in (easily found with a google search) that makes city driving very pleasant and does not harm fuel consumption. I found that with AFM active the truck seems to lack power since the delay from gas pedal input to acceleration is very long (has to downshift and go from 4 cylinders to all 8 cylinders)
When I cruise down the freeway, I just unplug the module (ODBII port) and it allows the AFM to work again. It does save fuel on the freeway to drop into 4 cylinders.
When I'm driving around the city or towing anything, I plug the module in again and disable the AFM.
Just some thoughts for you.
To clear things up a little- the newest generation of AFM is vastly improved over the earliest implementations (like any new technology).
The AFM on the 2014 GM trucks transitions in less than 20ms, which is for all intents and purposes instantaneous and decouples itself completely from downshifts when they are necessary (when the power demand exceeds the maximum available torque in V8 mode at a particular RPM).
Also, the new, redesigned 5.3L Ecotec engine makes more HP and torque than the old 5.3 (and in fact more than the 6.0L Vortec that still appears in the 3/4 and 1 ton pickups).
