"Wave1957- Thanks for the reply. I have not firmly decided on engine choice yet. My 97 GMC has a 350 and 4L60e and the trans made it 154K miles before needing rebuilt. It blew out that sun shell part. This 6.0 engine you mentioned; it's not a diesel is it? And this electronics stuff, well, my biggest problem with that is how do i diagnose a problem when something happens? I really want to keep by dash simple and use original gauges, but updated with new internals, maybe a couple extra gauges like trans temp and such. I don't have any of the programmers or diag tools in my toolbox. If my GMC throws up a check engine lite, i've got to head to the dealer. I don't like being unable to troubleshoot for myself. Now with all that said, these computer engines sure do run cleaner and sometimes do get better milage. And if it ends up being cost effective, more dependable, and a cleaner install, i'm definitely listening. Thanks,
And for both of you; What about that rear engine crossmember issue? How would each of you deal with that? I'm guessing that it would have to come out with the drivetrain that you suggest."
This 6.0 liter engine (which is 364ci) is a gas engine, available in 2500HD and 3500 Chevy GMC trucks; the biggest engine is actually now a 6.2 liter, around 340HP, but 6.0 a couple of years old are quite common in junkyard.
I understand your worry about maintenance, but these trucks are surprisingly reliable (first tune-up after 100000miles...). It is also a question, if you worry, to drive with a diagnostic tool with you instead of a screwdriver!... And there is still a lot of stuff bolted on the engine, not everything is electronics-only! There would of course be things for you to learn and adapt (fuel system, for instance), but that is hot rodding, too! Try the LS1Tech.com forum, in particular the "Hybrid" section (not the lectric ones, for vehicle that did not come from the factory with an LS engine!).
The aftermarket covers very well these engines, they are covered by great forums, you would find a lot of support for your install. This family of engines (often called the LS engines)started as Corvette engines (with aluminium blocks) then evolved into trucks (with cast iron blocks). They are not anymore some exotic thing... You should even be able to find engine mounts/headers... specifically made for your truck (although I do not know this for sure).
As for rear trans crossmember, I do not know your particular vehicle but when I put a 6.0 liter with 4L80e trans in my '70 Impala, I just moved the original Impala trans back a few inches using a pair of L bracket; the crossmember just needed 1 hole drilled.
