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1999 Suburban Coolant Leak

Hi everyone,

99 Suburban with 350/FI and 127K miles. Noticed a small oscillation in the temperature gauge about 2 mo ago, then one episode of spontaneous temps 220+ with loss of coolant. Now I have developed an external leak that appears to originate at the front of the passenger cylinder head-to-block interface. No CELs lit. No white smoke in exhaust, engine runs fine.

Any method of confirming this is the problem before comencing to pull the cylinder head? Is this a common problem during these model years with higher mileage?

Thanks for your time,

Carl

Reply to
Carl
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I'd be very surprised if it's the cylinder head gasket. The intake manifold gaskets are what is the common failure on these engines.

Ian

Reply to
shiden_kai

Most likely it is the intake manifold gasket and not the head gasket. Expect to see some slight surface damage to the intake manifold/head casting where the leak was occurring. You can use black RTV to fill in the rough spots when you install the new gaskets. It's not a terribly hard job to do on this vehicle.

Chris

Reply to
Hal

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