Chevy & GMC Vans

Wife got tired of fuel economy of 99 AWD Astro. Found an '02 Olds Silhouette with 82k miles for $6000 including tax, title, and fees. We owned two '97 Venture vans before we got her Astro. We liked 'em quite a bit.

I've heard a lot about bad lower intake manifold gaskets, part of the deal was they needed to flush and pressure test the coolant system. When i checked-out the van, the radiator cap had dex-cool goo on it, and the radiator itself had some sludge in it. I told them to re-fill the system with green coolant, too.

The manager called me and told me that his tech didn't want to put green coolant back in the system, because it was bad for aluminum radiators. I've never heard that.

They said that yesterday, the tech pressure tested before he drained it. The pressure test was okay. He then flushed the system and refilled it.. I think he said with the green coolant. He said the radiator is now leaking. The tech claimed it was because of the green coolant. I said it was because of that dex-cool crap. The flushing just removed the crud that was blocking the hole. #-o

So...
Is pressure testing good enough to know if the lower intake gasket is bad?
I see some evidence that the top of the engine has been serviced: out of place wiring and such. With it having 82k miles, that lower intake gasket may have already been replaced.... who knows.

I also found an '04 Venture with the 3400. The Venture has 76k miles, but has fewer options... and was priced at $9990. Should I dump the '02 for the '04?

Wait.. the sales guy for the Venture just called... that is odd.. he wants to know if I'll buy that venture for only $6900. Now they're making me think... only $900 more for an '04... hmmm

The TSBs I see for the lower intake manifold leak stops with '03. Does that mean the '04 won't have a problem? If the '04s may have the problem, too... then this 76k mile '04 is ready for the problem.

I'd really like to get the Olds, but does that radiator leak mean I'll be into the engine in a couple months?

Plus, TunerCAT has a tweaking module for the 02-03, but not for the 04

The Bible says to seek-out wise counsel. I guess you guys are better than nothing

Help me out, here....

From what I have seen over the last few years It does not matter what year it is, if it has the 3.4 you will be fixing those gaskets sooner or later. but everything is junk these days, so no matter what you buy it will have problems... except maybe a Sienna or an Oddysey, but then you are paying twice as much for the van... it is a toss up... Green coolant these days is not the same as what it used to be... it is now labeled universal and has been updated to work in place of dexcool... to my understanding anyways... good luck on the purchase!