Intake Manifold--Replace or Seal?



'02 Chevy Venture with 125K. It’s been dripping antifreeze for a year or two. It’s been a slow drip for most of that time but recently it’s gone from a few drops to a puddle under the car.

The shop said the intake manifold was leaking, from DexCool corrosion (I thought DexCool was only a problem if you saw it sludge up in your expansion tank). They said they could replace it for $600 or put a sealant in it for $75. The only problem is, it might clog up the heater core, which the shop said they would blow it out for free. I think this shop is trustworthy b/c in the past they’ve actually told me work didn’t need to be done when I thought it did. What are everyone’s opinions on this?


The intake manifold gaskets need to be replaced.

You may see the coolant leaking on the outside of the engine. But if it starts leaking on the inside of the engine where it starts mixing with the oil, the engine is toast.



I agree with Tester. Replace the seal. Just plugging the hole is a band-aid on a cancer, and can lead to a much more costly repair down the road. The seal has failed, and will only get worse, sealant or not. Replace it now, and be confident the other shoe will not drop later down the road.


I would not let them put the sealant in there unless I planned on dumping the vehicle soon. 125K still has a lot of life left. It should be fixed properly. Whatever the sealant is will likely do more harm than good. You’d be lucky if it just did nothing.


And I JUST noticed a few drops of oil on the garage floor this morning. The last oil change was several weeks ago. Is this heading to a larger problem?


No way to know without inspecting. The oil leak is probably something else entirely - could be big, could be small. A huge proportion of cars leak some oil - for most it is no big deal. You’ll need to take a look.


DexCool is notorious for ruining intake gaskets on many GM cars