The Truth About Aluminum Engines

[Tom Hitchcock]

Is it true that cars with aluminum engines almost never reach 200K miles without a blown head gasket, or hardly ever even reach 150K miles before the engine dies?  This, even assuming the operator performs all required maintenance when specified?  I'd hate to think my car's Northstar falls into this category!

Tom Hitchcock - CLC 2212 

[Dave Shepherd]

My N'Star experience seems to show that oil consumption and oil leaks are the number # 1 issues, then come the head gaskets and the head bolt threads in the block .  They do not seem to suffer " catastrohic failures" and can run for 250k.

[David King (kz78hy)]

I have an '97 Aurora w/the 4.0 engine that is a small Northstar.
So far it has 167k and leaks some oil.  I was late changing the coolant, but after that was done correctly, installing the sealing pellets in the lower radiator hose, the small coolant loss was solved. 

The cars average mileage is around 23 mpg for the last 14 years.

So, knock on wood and keep running those engines.

David

[Tom Hitchcock]

Thanks Gents. I appreciate your thoughtful and candid replies, but to be perfectly honest, I wasn't thinking of just the Northstar...although that certainly figures into the equation. True, my Northstar is also thirsty for oil, but there are no leaks...at least not yet. In contrast, my wife's Japanese car, with an aluminum 4-cylinder mill, has a head gasket that's just beginning to seep...not leak, but seeping.  Interestingly, her vehicle and my Eldorado have about the same milage but she's becoming real nervous about the reliability issue...and with good reason.  So, that's why I asked about these aluminum engines and their longevity.  Thanks again!

Tom Hitchcock - 2212

[Dave Shepherd]

Okay, you could try retorquing the head, but in time you will need a head gasket, some Asian all alloy blocks suffered head probolems but in general all of todays engine hold up well, the 4cyl. ( "buzz bombs") can wear faster as they are running higher rpms.

[Bob Steur]

Tom, lots of cars now have all aluminum engines - GM LS series for example - or aluminum head(s). My 94 Deville Concours has over 250,000 miles on the original engine, it's never had any internal engine issue. So I would say, not true.

I think the main difference is that aluminum blocks and heads will not take repeated overheating as well as cast iron.

[Tom Hitchcock]

Thanks to everyone for your input.  Your comments have been both helpful and appreciated.

Tom Hitchcock CLC 2212