What causes a bad intake gasket

Question

I have a 2004 f-150 & it failed emissions in our state it has to pass to get tags so luckily still under warranty i took it to dealer...they said it was a blown intake gasket ....I was just curious as to what might be the cause for a four year old truck to do that although it does have 63,000 miles as I go out of town alot. so any suggestions to help my curiosity would be helpful as searching it only brings me to replacement instructions...

Answer 1

The use of dissimilar metals has been a popular cause of failing gaskets in newer cars. Metals dissipate heat differently, and when you use a cast block with aluminum intake, you can have problems!

Answer 2

You're correct that a 4 year old truck shouldn't have failed already, but cars and trucks aren't built like they used to be. Still plenty of old trucks with 200-300K miles on them from the 60's and 70's on the road with untouched engines.

Farf is correct too, it's hard to seal dissimilar metals. Newer vehicles use aluminum intakes and often heads in an attempt to lighten up the weight of the vehicle. The result is an engine that is more prone to failure than say an old Ford 390 or Chrysler 225.

But that's "progress".