I need information, the gmc envoy has 4.2L, will it fit a '01 gmc jimmy? I have an engine lock from a '03 trailblazer, will the wiring of the jimmy work for the 4.2L? Is it possible, if it is what kind of big mods will I need to do?

 

sure it'll fit.

but it ain't gonna be a simple job.

and that was just a typo, right? you meant engine block?

for starters, you're gonna need the trans and computer as well. plus you've got custom engine mounts & trany mounts to build, convert over to electric fans. none of the wiring in the engine bays are gonna be the same, so you'll need the wiring from a truck as well.

do you see where this is going? you're basically gonna need a complete truck for the task.

and from experience, unless you've done quite a few custom jobs, it can be quite a headache. especially when it comes to the wiring.

 

Good luck trying to shoehorn that 4.2 into the engine bay of an '01 Jimmy. The 4.2 is an I6 and the 4.3 is a V6, so the length difference is quite a bit.