Well, after battling with GM and intake gasket problems over the last decade, GM now has head gasket problems on most of the late model high value V-6s, both the 3.5 and 3.9 liters. If you look at some of the GM forums and Edmunds, many people are reporting head gasket leaks. I just got the confirmation from the service manager at our local Chevy dealer that my moms 2007 Impala with the 3.5L needs new head gaskets, a new water pump, and new coolant crossover pipe gaskets. There are 2 very important TSBs for these engines for the head gaskets and the coolant crossover pipe gaskets. It appears the problem rivals the intake gasket problems, so if you guys with any of these engines are noticing coolant loss, fluctuating or non existent heat from the HVAC (air pockets will form in the heater core), and external leaks, get your cars into the dealer ASAP before your GM 5 year/100K power train warranty expires.
I'll say this: at this point, the dealer isn't fighting the warranty at all and they're explaining everything to me since I'm well informed about the problem. Thank goodness GM has the 5 year power train warranty.
Here's the list of engines and vehicles that have these engines.
http://en.wikipedia.org/wiki/GM_High_Value_engine
The TSB for the head gaskets is 4196. The TSB for the coolant crossover pipe gaskets is 07-06-02-006A.
I'll say this: at this point, the dealer isn't fighting the warranty at all and they're explaining everything to me since I'm well informed about the problem. Thank goodness GM has the 5 year power train warranty.
Here's the list of engines and vehicles that have these engines.
http://en.wikipedia.org/wiki/GM_High_Value_engine
The TSB for the head gaskets is 4196. The TSB for the coolant crossover pipe gaskets is 07-06-02-006A.