Originally Posted by yutzybrian
Head studs. The method GM used form the factory fails anywhere from 50k up (mine is 128k and no issues yet). The studs start pulling the sleeve up which causes the entire head to lift off the deck (obviously nm in amount, so not visually noticeable) which leads to gasket failure and coolant leaking into exhaust. I plan on rebuilding mine later this year or early next. $289 for the permanent fix
, which permanently mounts the studs to the block with large coarse threads. One time job and done. The Northstar sounds amazing (especially with my Flowmaster 40s) and is fun to drive for being a FWD car. Not saying the 3800 motor is bad (I might be getting one for a project that is in the works) but the Bonneville deserves a V8.
Not sure there is a permenant fix for the N*? The first head gasket went at 122K miles as anticipated failure, but one year and 30K easy miles later with studded
heads by "claimed" N* expert the second head gasket failed.
Personal opinion is find a different auto, one that does not have a N*
. Got nearly 300K out of my 3.8 in a 95 Olds without
any major work to engine. LOL
Still in process diagnosing the cause of second HG failure.