If your Montana has run well on the original "factory" plugs for that
long, Why would you want to try any other brand or style? I think the
engineers at GM got it right. Over the years I have solved many
problems by replacing optional plugs with original style and brand
plugs. I have only been repairing cars since 1977.  Your van uses AC
delco #41-101 plugs for about $6.50 each. I would recomend replacing
the plug wires at the same time since they are most likely just as
old.

If the factory ones worked well, I'd stick with those.  there is a real
difference in plugs, but it works both ways - I've had poor luck with
Champions in older cars (flood the engine once and the plugs are never
the same) but some of the highly priced plugs are either just gimmicks
that separate you from your money (Splitfire being an example that comes
readily to mind) or else may be platinum plugs which aren't appropriate
for all applications (again, they do not work well in older engines)

I know some of my comments above don't directly pertain to your car, but
my real point was, if the stock parts worked well, and you're not
hot-rodding it, why pay more for replacements?

nate

In article
<1194687983.244560.75450@o38g2000hse.googlegroups.com>,

The correct plug for your van is the stock AC Delco 41-101 as
mentioned in another post.

If you're going to change them yourself, you are in for a whole
new experience in pain, agony and frustration.  Do yourself a
favor and put the ACs in, the buck sixty-nine spark plugs aren't
going to last very long.

How's the coolant holding up?  At 115k miles, the intake manifold
gaskets should be leaking coolant if they haven't been changed
already.  You may want to investigate further before you get too
committed to this van.

There is a real difference, and on some vehicles you may find that
spending the $80 gives you a car that runs a lot worse, while on others
you may find that it gives you a car that runs better.

Obviously whatever is in there has been serving you well.  Buy whatever
you used last time.  Or buy whatever brand Pontiac recommends.
--scott

use ac delco platiums or ngk platiums and take it some were to have it
done
it will take you on the ground to change plugs at least 6 hours trying to
get to the rear plugs

Use AC Delco 41-101 platnum plugs.
they are OE, the are designed for your motor and will last another 80,000
miles.
Replace the wires as well, you DO NOT need to waste money on AC Delco wires,
any quality brand will work just fine.

you are paying more for a platnum plug vs a copper cored plug, and also the
AC Delco name.