: month and day of midyear headbolt change in 2003



luvoldcaddybuthate03
08-02-10, 08:40 PM
Does any one know the date that production changed to the courser threads on the head bolts? I have a 2003 base deville with blown head gasket. engine born on 25 august 2002. (sticker has date on right head). I have a engine out of junk yard with a born on date of 15 october 2002. I was just wondering if that was after the midyear change? There are several other engines at the junk yard with around the same dates (oct, and Noc 2002). It is HELL to change these engines out and only want to do it once. Any body know??

Many thanks!!!

Ranger
08-03-10, 12:06 AM
Don't know the date, but the thread pitch change came in '04.

zr1mark
08-03-10, 10:49 AM
Fix the engine in the car...........Don't ask me how I know. I also put "another" engine in my car and got approx. 15,000 miles on it before the headgaskets went...

Submariner409
08-03-10, 11:42 AM
Install a set of Jake's studs and, regardless of the engine year, the head bolt thread size becomes moot.

tateos
08-03-10, 01:10 PM
Fix the engine in the car...........Don't ask me how I know. I also put "another" engine in my car and got approx. 15,000 miles on it before the headgaskets went...

Yep - fix your current engine - I did what Mark did - got 23K miles out of my used engine before the HG blew. I repaired that engine, and have driven 16K trouble free miles since.

luvoldcaddybuthate03
08-03-10, 07:59 PM
Install a set of Jake's studs and, regardless of the engine year, the head bolt thread size becomes moot.

I'm sure Jakes studs are great, however, the cost of me tearing the rest of the engine down, doing the machine work, replaceing seals gaskets etc. and it would still burn oil and would not be worth it at all!!! The engine I got has 23000 miles and has a 3 year warrenty or 36000 miles which will be enough time for me to get rid of this piece of shit. I just have NO faith in cadillac anymore or GM either (and I'm a lifelong GM man). Problems started with this car just after the factory warrenty ran out of time (not miles!) and GM told me to pound sand! Studs work!! always have!! So why didnt those stupid bastards at GM put then in back in 1995 when they knew they had a problem? They didnt care and thats why we the TAXPAYERS own there sorry asses! I wound'nt be screwing with this at all, but, because I took REAL good care of the car and it is still beautyful, and has OK trade value. If I tried to trade it or sell it with the blown engine I would get shit for it. Really guys I'm thankful for the input and sorry to rage like this, I just got the engine out (after 2 days work) and am a little cranky! I would still like to know when the change was because if one of the other avaible engines has it I will put that in and the next guy might get a good car, even thou it hasnt been for me at all! again Many Thanks

Ranger
08-03-10, 10:26 PM
I would still like to know when the change was
See post #2. No '02 engine will have the upgrade.


Studs work!! always have!! So why didnt those stupid bastards at GM put then in back in 1995 when they knew they had a problem?
Studs are not conducive to assembly line engines from what I was told by our old Guru.

luvoldcaddybuthate03
08-04-10, 08:33 AM
See post #2. No '02 engine will have the upgrade.


Studs are not conducive to assembly line engines from what I was told by our old Guru.
Thanks for your response, I believe 1 one the three engines at the boneyard was made in march of 03 so that should have the change?

And... as far has studs being "not conductive" to the assembly line... I just find that very hard to believe!!! Other makers use studs in there engines! Im no expert by any means but you still need drill and tap a hole in the block so what differance would it have been put in a stud instead of a bolt? Its "not Conductive" to good business to keep makeing and selling a clearly defective product, specially when you know about the problem 10+/- years running
It is stupid to build a engine with this much technology and electronics (more than a moon rocket) and not fix this! Are they a marval? Sure they are!! they make close to 300 hp and only weigh 400 lbs!! but what good does it do?? I would never fully trust a Cadillac with a factory northstar on a long trip ever again. In other words I dont buy it!!! I still think GM just didnt give a shit and they were hopeing that when the HG's blew at 50 or 60 thousnd we would just go out and buy another brand new Cadillac! well screw them!!! Its OK to do that if you can afford it, I cant, I bought this car because I thoght it was a good car that would last me at least 100000 before needing work, just like my old Cadillacs! I do thank you for the info Ranger

Ranger
08-04-10, 01:23 PM
The tread pitch change was in '04. When that production actually started, I have no idea.

I tend to agree with everything you say about the studs and the problem. As I said, that came from our old Guru, but he was about as dedicated a GM employee as one could find.