Today, I talked to the mechanic who replaced my lower intake manifold gasket a few weeks back. I asked him for his opinion. "What's the skinny on the 4.2 gasket problems?" I asked.
In summary;
The '97 and early '98 engines just had poor quality gaskets.
The newer gaskets are way better.
The gaskets are a hard plastic-like material with a rubber o-ring molded into the gasket.
After much time, the gasket gets brittle and small cracks form, or pieces get eaten away.
In due course, the 0-ring gets exposed and a small section will get "sucked" into the intake stream.
This provides the path for coolant.

That is what he found in mine. The gasket near the number 2 cylinder had a very small section of o-ring that was torn. This allowed the slight coolant leak I was experiencing.

I realize this is ONLY MY EXPERIENCE. But,the guy is competent and honest.
I have formed my opinon (Thomas, are you listening !?):
If I had any 1999-2004 4.2, I would at the least, keep a very close watch on the coolant level. Most problems appear to give warning via slight steady coolant loss. HEED THE WARNING SIGNS - get the gasket replaced - soon!
If you really want to be proactive, budget $300 or so for gasket replacement before it fails. One might argue "I shouldn't have to replace a gasket at 130, 140 or 150,000 miles." And you know what? You would be right. You shouldn't have to - but maybe you have to anyways.

For me, having spent a whopping total of $500 for repairs in 158,500 miles, the gasket issue is a no-brainer.
I have had to spend $1,100 to have an transmission rebuilt in an Explorer at 80,000 miles. I'll take the gasket over the tranny any day.

These are just my thoughts and opinions. As I often say.......

Your results may vary.

 

I agree Brian, as you have heard me say before, I am proactive in my maintenance. I have a steady coolant loss, but it's going on the ground. The new hoses I put on last spring must be of poor quality, because both the upper and the lower will occasionally work loose and leak.

 

Brian,ive done alot of research on this gasket issue,but yet to look into the material they are made from.I know they are plastic based with rubber o-ring type seals for the ports.And,the old gaskets are thinner then the newer gaskets. What my question is,did your friend say if the newer gaskets are the same material or better and improved? If they are the same,then people like me,who have replaced mine already,will face this problem again in the future.
I think this would be an interesting subject to look into and post the results.

 

thanks for the info. now where are the pics of the 05?