I bought a 2005 Pacifica with the 3.5 engine. I see now that just to replace the spark plugs involves removing the intake manifold. Pardon me for being 'old school', but what idiot designer came up with this idea?

When I first starting looking at the Pacifica cars I looked at one with the 3.8 liter engine. I was pleasantly surprised when I first opened that hood and discovered a engine more like the old ones I used to work on, where things were accessible.

So I have several questions:
1) Is there some conscience as to which engine (3.5 vs 3.8) is the better of the two?
2) Are they interchangeable in the vehicles, or are the drive-line connections totally different?
3) Are these engines difficult, or real expensive to rebuild??

I'm asking these questions in advance as I like my vehicle, and hopeful want to keep it for a long time (the rest of my retirement).
Thanks, Brian

 

3.5 timing belt 3.8 chain
are not swapable electronics are different along with the computer. the cost is about the same id say I just got done a few months back r and r heads because some one ovea heated the 3.5 and warped teh heads.

 

is one better that the other? Are both 24 valve engines?


So engines not swapable in a chassis because of all of the supporting electronics?