11th Sep 2007, 21:02

Just so you know the Northstar engines are all aluminum. Heads and block.

14th Dec 2007, 07:07

The Northstars are all aluminum. The reason for most blown head gaskets on these cars is because people do radiator flushes on them, and don't replace the anti-freeze with the recommended DexCool. Theres a reason GM and your owner's manual tell you to use DexCool ONLY. If you neglect to follow instructions, your bound to have problems.

26th Dec 2007, 00:13

The Northstar engine is a fine engine. It's derived from the LT-5 Corvette ZR-1 engine and has the exact same block. I had a 1990 Corvette ZR-1 that went 0-60 in 4 seconds flat. I now have a built 1993 ZR-1 that does the 1/4 in 10.57 (timing sheet) and 0-60 in 3 seconds. (You can watch it on You Tube). The LT-5 engine is bulletproof and the block and heads are the best part, just beautifully crafted. They are the foundation of the Northstar. IMO, improper maintainance will kill any engine, especially a fairly sophisticated jewel. If you have a car that is 60 grand when brand new and then skimp on the most basic of repairs when you're the 3rd owner, well guess what? KaBoom! You can't neglect a diesel, so why neglect a Caddy?

11th Jun 2008, 10:30

I am thinking of buying an Eldorado with this very engine. Although I am a little put off by the head gasket posts, I will make sure I find one with the correct maintenance done on it.

I know that the Northstar is the best V8 design on US roads, and I've read many rave reviews on the car itself. Why spend 3X more money on a Japanese copy when you can get an elegant, and superb quality car that is US made.

Unlike some people that post here, I have pride in the US worker and engineers. I feel they work the hardest and have the most creative minds. I take pride in what I do at work, and I feel that I am the best at what I do.

Plus, true status isn't Japanese!!! Maybe a Rolls Royce may have more status, but not too many of us can afford one!

I think Cadillac is the best with the most cutting edge technology, not the Japanese.

8th Jul 2008, 21:53

If you're going to buy that Eldo (or already have,) make sure the *first* thing you do is drain, not flush the coolant, replace the thermostat, cap, hoses & clamps then refill with Dex-Cool and GM seal tabs. You don't *ever* want this engine to overheat, so take all precautions necessary to insure it doesn't. The first time is likely to build up enough pressure/ heat to blow head gaskets.

I've owned '94 and '99 Eldorados, and the head gaskets went on BOTH! If the temp climbs, pull over immediately and get it towed and checked out - it's much cheaper than a $3,000 head job with time serts. Engine must be pulled.

Another problematic issue with these cars is the suspension. The front end starts rattling and bouncing, requiring huge sums of money to replace the da*n air shocks.

I love the appearance of this body style Eldo - it's timeless, American & Classic. A great combination of elegance, muscular power and sportiness. 300 HP in style. But there's a reason these are affordable now - they're gong cost big time when they DO break down. It's a love - hate relationship.

5th Sep 2008, 19:06

Bad engine design? The design is excellent. It was 15 years ahead of its time. Like many others have said, the Northstar is all aluminum. That would be your first problem. You don't know enough about your own car to properly maintain it. And maintenance, ahh yes. Remember that time you took your Eldorado to PepBoys for that coolant flush and you opted for cheap run of the mill coolant rather than the REQUIRED Dex-Cool? And the stupid a$$ mechanics if you would even call them that didn't know enough to realize this? So here is how it goes. You went cheap and instead of taking your car to an authorized Cadillac dealership, you take it to a Jiffy Lube or whatever. You go for the cheap coolant as I already stated. Not only is the mechanic not intelligent to realize that the car requires Dex-Cool, he also doesn't realize that after you flush the coolant on these engines, they require GM Sealant Supplement (some call them pellets). This supplement, well, it re-seals anywhere coolant can leak from. They are placed in the lower heater hose and the car is run for 15 minutes at operating temperature as the pellets dissolve as they flow through your cooling system. So now you have a cause an effect here. Cause in most cases being no pellets. So you spring a coolant leak that you have no idea about until its too late. Here comes the effect... BAM!!! There goes your head gasket because you dumped all your coolant on the ground and your car overheated. And all because you wanted to save a few dollars by not going to the dealership.

This is coming from a GM and ASE certified master tech and Cadillac specialist. Have I done a lot of head gaskets on Northstars? Hell yea! And I have made a crap ton of money doing so too. BUT, every one I have seen was because of the scenario stated above. And that's why the head gasket problem was never recalled, because it was never a manufacturer defect.

What so many people don't realize is that when you buy a high end car, it cost more for EVERYTHING. When you bought that Cadillac, Mercedes Benz, BMW, etc. you also bought image, class, prestige, and a brand name. Yes that's right, your paying for the name. You have to spend the extra money to maintain the car, or it will kick you in you're a$$. They have a personality of their own you know:) If you don't want to, well go buy an Aveo then.

25th Sep 2008, 18:13

The design of the Northstar engine is flawed. No engine American or foreign has as many problems. It is designed to be taken back to GM for all repairs. Yes I bought one and never will again. Do not buy whether you are rich or poor.

15th Oct 2008, 08:06

I have a 1999 Seville with a leaking head gasket. I'm thinking about using one of those liquid sealing products. The manufacturer says to flush the coolant system, put in their product and then replace the coolant, but don't use Dexcool.

Anybody have any thoughts?

7th Mar 2009, 21:22

I own a 99 Seville with 154,000 miles. It too has developed this problem although it hasn't overheated yet, it has taken to drinking antifreeze. The car has always been maintained and the system has been refilled with 50% Dex-cool and 50% water with the 3 sealant/conditioner tablets in the bottom hose. The engine has never been ran hard until it is up to full operating temperature and then only on rare occasions, it has never been shutoff after and heavy throttle usage without a cool-down first. By hard running I mean full throttle to 60 or 70 mph, not a top end run, my car has never seen high speeds over 100 mph.

It is my conclusion based only on my experience and what I've read that this widespread problem is not caused by neglect or abuse or as stated elsewhere "stupidity", it is just a problem inherent with the design. As I understand, the newer than 2004 North-stars do not have the problem because the design of the head bolts has been changed.

I really wish GM would do a recall of the affected vehicles so I wouldn't have to ditch mine, and also because this problem has the ability to really damage Cadillac's image.