Re: Cracked engine block on 2000 Cadillacs
See attached photos. Hopefully this helps.
I did make a mistake. Joe at Midwest Cadillac Repair has not had three 2000 Cadillacs with cracked blocks out of six. After reviewing his records last night, Joe has had three 2000+ cracked blocks out of seven 2000+ Cadillacs. Within the past couple months, Joe has had the following cars come in with cracked blocks:
1) a 2001 DeVille... ~150k miles, dexcool in it but not full, no freeze damage,leaking out the front, engine oil was ugly maybe because it was sitting, seemed like a neglected car.
2) a 2000 Deville... ~100k miles, dexcool full, no freeze damage, leaking out the back, inside of engine is perfect, has original plugs, overall very clean car.
3) my 2000 Eldorado... ~120k miles, has dexcool almost full, leaking out the back (see photo), overall very clean car. It was very hard to take a clear photo. The length of the crack is unknown.
The above just seems like too great of a coincidence. If Joe is that special, then I need him to choose the PowerBall numbers.
Looking at the blocks from the outside, the pre 2000 blocks appear much beefier than the 2000+ blocks. Yesterday, we used a hammer and smacked the 2001 block at its crack until it broke. See photo. The aluminum block at the point(see screwdriver in photo) it broke away in the photo is only 1/8" think. Yes, only 1/8 of an inch. Then you have about 1/8" of space before the steel sleeve. I am not a metallurgical engineer, I don’t play one on TV, and I did not stay at a Holiday Inn last night. But, it doesn't take much to conclude that if you thin out the block and then have an aluminum composition that is "harder" than the previous "softer" aluminum, the end result will not be positive. Maybe it just takes time and enough heat cycles for the 2000+ blocks composition to get fatigued; what if ~ 10 years is the average time, and is the "beginning of the end" of the 2000+ N* blocks? If over the next few years people begin to see more and more of the 2000+ N* blocks with cracks, there will be a definitive answer based on fact and not mere speculation. Understandably, it is very difficult to create a conclusion based on photos and I think this or I think that. We will never have a GM engineer come and explain things as they truly are because to do so would involve liability issues and revealing trade secrets. But, one thing that I can say for 100% certain is that there are three 2000+ N* cracked blocks at my friend’s shop out of 7 2000+ cars (those 7 cars being within the past 6 months total – cracked block cars within 2 months). BTW, that hairline crack on the 2001 appears to be right where the head bolts would end. So, further theorizing could easily point in the direction of... 2000+ N* block's head bolts are holding very well compared to pre 2000, structural integrity is lost in the 2000+ blocks over time (albeit heat cycles or "hardness" of the new aluminum composition), and the combination of the two results in these cracks.