2003 Buick Century is near 100,000 mile marker. A mechanic told me the manifold gasket is leaking externally, and if I don’t repair quickly, will leak internally and mess up my motor. Is this a true statement? Is this a common repair job for my make and model car? How can I validate?
Is this the exhaust manifold or the intake manifold?
If your mechanic is talking about the “intake” manifold gasket, he is correct. If the coolant gets into the oil, it will displace the oil from the engine bearings. It was common problem for a lot of GM products in those years.
GM settled a class action suit to cover some of the repairs last year. Unfortunately, Aug or Sept 2008 was the latest date to submit a claim. Here is a link for info:
I had the intake manifold gasket replaced on my 2000 Blazer not long after I bought it used. The Blazer was losing about a pint of coolant a month. At the next oil change my trusted mechanic found a small amount of coolant in the oil. He strongly recommended changing the gasket immediately before any engine damage occurred. There was nothing in it for him since he suggested I have the repair done at the dealer. The dealer split cost of the repair as a goodwill gesture. Six years and 60k miles later, there have been no further problems.
P.S. Do a search on “intake manifold gasket” on this forum or Google for more info.
Get a second opinion from a qualified mechanic.