03 DTS head gasket failure prevention ?

[skankyfrankie]

Does it exist, if the correct coolant & Tstat is replaced every 2 years, it if never overheats are they still going to fail, will the head bolts still pull out?

If the answer is no then I feel much better about this car

If the answer is yes then I have a really nice 03 DTS with 23K on it for sale $21K. lol

[chubbyranger]

From everything I've read here if you do what you said and add the Barrs supplement when you do the coolant service you should have a much lower probability of HG problems.

[JimHare]

Frankie, first off, you really can't base overall statistics with what you read on this forum (or any i-net forum, for that matter). It's like going to a hospital and thinking, "My god, everyone in this city is sick..." - the hundreds of thousands of Caddy owners who've never had a HG problem tend not to search out forums and complain that their cars never need service, if you get my drift.

That said, cooling system maintenance is a little more important on these cars, or any cars with all aluminum engines, due to the greater stress placed on connections by the thermal cycling. Aluminum expands and contracts to a greater degree than does the old fashioned cast iron, so it's very important the the mating surfaces between parts of the engine, such as gaskets, do not lose their integrity. HGs loose their integrity when the coolant system has lost the ability to keep corrosion at bay, and the coolant system loses the ability to keep corrosion at bay when it gets old and depleted.

Thus, a fresh filling of Dexcool every 3 years is probably about the best advice - it can go longer, but for about $20 a change, why risk it?

The Bars Leak tablets are for "nuisance" leaks - around hose connections, tiny porosity leaks, etc etc. They were recommended by GM up until around 2003 or so, but a tube of the stuff popped into the radiator hose when you change probably won't do any harm.

Be sure you don't add the stuff to the expansion tank - it will simply clog up the line. The expansion tank doesn't have enough action of coolant coming in and out to work right. Has to go in the hose.

Keep an eye on it, and enjoy it. Don't obsess over what you read here - unfortunate souls who have a HG problem will seek out forums like this, and I'm not trying to minimize their woes - but you can't read that as the norm.

[skankyfrankie]

Thank you all, and to quote my wife " if all else fails thats what that 7 yr 100K warranty is for so knock it off, your not selling my baby" LOL.

[Destroyer]

Originally Posted by JimHare

Frankie, first off, you really can't base overall statistics with what you read on this forum (or any i-net forum, for that matter). It's like going to a hospital and thinking, "My god, everyone in this city is sick..." - the hundreds of thousands of Caddy owners who've never had a HG problem tend not to search out forums and complain that their cars never need service, if you get my drift.

That said, cooling system maintenance is a little more important on these cars, or any cars with all aluminum engines, due to the greater stress placed on connections by the thermal cycling. Aluminum expands and contracts to a greater degree than does the old fashioned cast iron, so it's very important the the mating surfaces between parts of the engine, such as gaskets, do not lose their integrity. HGs loose their integrity when the coolant system has lost the ability to keep corrosion at bay, and the coolant system loses the ability to keep corrosion at bay when it gets old and depleted.

Thus, a fresh filling of Dexcool every 3 years is probably about the best advice - it can go longer, but for about $20 a change, why risk it?

The Bars Leak tablets are for "nuisance" leaks - around hose connections, tiny porosity leaks, etc etc. They were recommended by GM up until around 2003 or so, but a tube of the stuff popped into the radiator hose when you change probably won't do any harm.

Be sure you don't add the stuff to the expansion tank - it will simply clog up the line. The expansion tank doesn't have enough action of coolant coming in and out to work right. Has to go in the hose.

Keep an eye on it, and enjoy it. Don't obsess over what you read here - unfortunate souls who have a HG problem will seek out forums like this, and I'm not trying to minimize their woes - but you can't read that as the norm.

I dont know Jim. I'm on a few different car forums, most recently one for Lincoln Mark VIII's and yes people come to talk about their cars and repairs they need help with but there is no 1 general consistent problem (especially Head gaskets) that almost everyone on the forum is having problems with. Hek, I'm also on the RWD section here for my '91 Brougham and the posts are usually on how to modify the car or replacing simple parts, not the chaos that goes on in this section. The Northstar has a great reputation for being a strong, powerful motor but at the other end it also DOES indeed have a reputation of blowing head gaskets and being extremely hard to work on. Every mechanic I went to hates working on them and they are ALL familiar with the H/G issue.

[skankyfrankie]

Thanks Destroyer, your name really fit you LOL.

[JimHare]

Well, all I know is I have 362,000 miles on three Northstars since 2001, my neighbor has a 97 SLS with 189,000 miles on it and I know half a dozen other people with mid 90s to 2006 Northstar powered cars. Between us we probably have close to 1,000,000 Northstar powered miles, and not a HG among us.

Perception is not reality, in this case. Again, you have to balance actual numbers - I have to disagree with your statement

There is no 1 general consistent problem (especially Head gaskets) that almost everyone on the forum is having problems with

I would doubt that more than 20% of the members here have had NS Head Gasket problems.

Thing is, if you Google "Cadillac Head Gaskets" guess what site comes up first?

Thus, if people have a problem (and mind you, I'm not saying there are no problems), this is the first place they come to. Skews the numbers all to hell.

Mechanics hate Northstars (and any large, complex, cramped engine) because they're harder to work on, and require a little more brain cell than the old SBCs they're used to.

It's not suprising that mechanics are familiar with the "H/G Issue" - since they're the ones that work on them. But I can guarantee you that there ain't a mechanic with 200 miles of me that's "familar" with my N/S because at 80K miles, it hasn't cost me one thin dime except for a battery two years ago.

[Destroyer]

Originally Posted by JimHare

Mechanics hate Northstars (and any large, complex, cramped engine) because they're harder to work on, and require a little more brain cell than the old SBCs they're used to.

Jim I dont believe they require more brain cells to work on, what they require is more cuts and scrapes, a lot more cussing and a good dose of patience not to mention the alcohol consumption that follows. The cramped engine bay IS what makes these cars so impossible to deal with in the event of a Head gasket failure or almost any repair. If it was a RWD and there was room to do the job in the car, it would have been a much a better car. I think you have been very lucky with your N* motors and thats a good thing. Its a roll of the dice with these cars and you are one of the lucky ones thus far.

[skankyfrankie]

I do have to wonder when Timecert makes a N* specific kit. Seems to be a good indicator of a lot of problems. However I can see the side about people only come here if they have problems. Either way I am changing coolant & T stat every 2 years and using Norosion once per year. I do believe aluminum is more easily damaged by any overheating.

[JimHare]

Originally Posted by skankyfrankie

I do believe aluminum is more easily damaged by any overheating.

Ya see, there's the key to the whole thing right there - aluminum expands and contracts a great deal more than cast iron, so maintenance of the cooling system is more important - bad coolant, weak anti-corrosion, greater thermal movement, corrosion hits HG, coolant leaks into head bolts, corrodes aluminum threads, there ya go.

Whatever you decide, good luck and have fun with your ride.

[JimHare]

Originally Posted by Destroyer

Jim I dont believe they require more brain cells to work on, what they require is more cuts and scrapes, a lot more cussing and a good dose of patience not to mention the alcohol consumption that follows. The cramped engine bay IS what makes these cars so impossible to deal with in the event of a Head gasket failure or almost any repair.

Yeah, but you could say that about nearly ANY transverse V6 or V8 in most FWD cars - they're crammed in there, full of wires and cables everywhere, power accessories, batteries, washer fluid tanks, etc etc etc.

At least they had the foresight to put the starter up in the valley where it's a helluva lot easier to get to. I remember cussing a blue streak when I had to R&R the starter on a 65 Plymouth Fury. You could have had a roller derby in the engine bay around the motor but everything down low was impossible to get at.. .lol

[Playdrv4me]

I dont think it is fair to blame aluminum engines as a whole either. Lincoln's "Intech" V8 which for all intents and purposes is viewed as Ford's answer to the Northstar (and usually in an inferior light), doesnt suffer from anymore headgasket or overheating issues than the average cast iron engine. Save for some issues with the coolant passages leaking, it is a pretty bulletproof motor. I owned two of them... Once in my 1996 Continental, and then in my 1997 Mark VIII, both of those cars had in excess of 130k when I got rid of them (the Mark had close to 160), and I never had a single issue with the motor. Now mind you, everything ELSE around the motor fell apart... but its one of the few powertrains, along with BMW's 3.0L I6, that I have not a single complaint about. I will ADD to that, that once the Continental left my hands, my brother really neglected the car completely once the paint went... no coolant changes, no oil changes, nothing. The first time he did ANYTHING to it, was when it FINALLY WOULD NOT START from having gone so long past its tune-up interval that the plugs and wires were completely toast. It never smoked, sputtered, overheated, smelled or anything else even with this abuse.

Its such a strong motor that Ford sees fit to use it in everything from performance vehicles (Cobra) to SUV's and even Full Size heavy duty trucks. The 5.4L Triton V8 in fact is based upon the architecture of the 4.6. It is *the* Ford corporate motor. GM on the other hand, chooses its Northstar applications cautiously, and chooses to use tried and true OHV technology in their V8 performance vehicles and trucks. The Northstar has ventured out of the realms of Cadillac-dom only a few times in its 15 year lifespan. The Aurora, the Bonneville GXP, and the Buick Lucerne are the only applications outside of Cadillac's bread and butter cars where the engine has been used to any extent. All light duty luxury sedans. The red herring would be the *extensively* modified version of the NS utilized in the XLR-V and STS-V, however these vehicles do not represent the majority and feature hand built, limited production motors.

Read between the lines though, and youll see that I think it is truly a world-class powerplant... it just has some inherent flaws that only now are beginning to be addressed. I dont think anyone who has replied in this thread has been wrong, Destroyer and Jim both have very valid points. I would tend to aire on Destroyer's side of the boat though in saying that this is in fact one of the few cases where the posts on this forum actually reflect a larger overall problem, rather than some sort of microcosm or mere "sampling" of a few problem cars. I had 4 Northstars three of which had the dreaded cylinder misfire code at some point, all of which used coolant more than they should have, and one of which actually had a head leak. Im not by any means talking out of my ass here.

I've also addressed this a few times... but there seems to be a general misconception that post-2000 motors are immune from the head issue. I think there was a real measurable improvement with regard to case half oil leaks on the later models (in itself a real embarrasment for an engine of this caliber), but the headgasket issue continued through at least 2002. I have not seen any 2003's with this problem, but not a whole lot less 2000-02's. I had a sincere hope that 2003 and up had somehow been resolved, but according to some of our resident gurus here, theres not supposed to be any difference between the 2002 and 2003 motors. We will just have to wait and see how it turns out.

The bottom line is this is a fantastic engine and the Ford 4.6 just doesnt top it in terms of smoothness and absolutely linear power delivery. I also would not trade a Seville for a Continental no matter what. Its a ton more car and a hell of alot better looking. You merely have to understand that for better worse, the design of this motor requires more diligence with maintenance *AND* a KEEN eye when your shopping for the car to begin with. It does no good to follow a religious coolant maintenance schedule if it wasnt maintained prior to your ownership.

[Destroyer]

Well said!