I bought a 1993 STS that had 203,000 miles on it. It don't heat up and runs about 198 degrees, I only seen it at 201 degrees once and only uses about 1-1/2 qts of oil per 3000 mile change. It does have very clean green anti freeze in it and it runs very nice and smooth. My question is could I assume that the head qaskets were already replaced, could it possibly go that many miles without gasket replacement? If they were replaced and the head bolt kit installed are these engines good to go almost forever then? I really am surprised it don't need them and I bought this car expecting to have to replace them but maybe I got lucky.
Thank You

 

if the car was properly maintained, specially changing the coolant every two years ignoring the GM 10 year thing, the engine can and will most likely go 400,000 ++ miles ...

we have lots of 20 year old engines doing just fine, never having been opened .. but they all seemed to have ignored the GM 10 year thing and changed coolant often.

check these valuable threads, special interest for you is the My Cad has more miles, headgaskets and coolant threads.


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Why you should change to coolant the day you buy the Cadillac.
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Cadillac GM e-ghosts electric problems, intermittent codes, etc.
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Help from our TECHs ? You really want to read this.
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Cadillac TECH FAQ MENU .. pull up all the FAQ topics
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Cadillac Technical FAQ section .. everything Cadillac
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The Cadillac Allante Pub - discuss, argue, and laugh .. Allante not needed to jump in.
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Allantesource.com Allante PROCEDURES MENU .. issues that few know how to handle
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Hobby Corner .. Hot wheels, trains, whatever ..
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If you start adding up how many Northstars have been produced since 1993, thats 15 years, even if the number is 150,000 cars per year which is what one plant needs to be viable that is2,250,000 engines. You only hear about the ones that go bad. Have you heard two million stories?