14th Sep 2003, 20:27

Okay, you asked, you got it. IT'S NOT THE TIRES!!! Make of tires have NOTHING to do with a vibration problem. The only difference is if you put a tire designed for another application on. For instance, you put a performance tire on a luxury car, it'll ride rougher, though not to this extent. I suggest, if it hasn't been done yet to get the car put on a proper balancer that goes under the wheel assembly while still on car, this is called a Dynamic Balancer. It will rotate the entire wheel/tire/rotors, etc. If there's a problem with the rims, that could be it too, as it wouldn't be due to using any particular make of tire. Yes if you put a cheap tire on it could happen, but that doesn't sound like any of you have done this.


14th Sep 2003, 23:58

Just had a thought. (UH OH!!) I wonder if it would help to rotate your tires? Sometimes a rim (especially on a large car) can differ in balancing by 2 1/2oz or more!! If it's bent it could even be worse. Just an idea, occasionally it's even been known to work.


26th Feb 2004, 20:51

I have a 1996 Cadillac De-ville with a North Star Engine. I have a problem with the head gaskets per the mechanic at a local Cadillac dealer. He said that the head bolts has come loose, and this is a problem that GM is having with some of the North Star Engine. It is going to cost approximately $3500 to correct this problem. I would like to know if any one have had this problem. I also have the problem with oil consumption, but have not been given the reason why.

11th Apr 2004, 13:09

We also have the Uk spec model STS, RHD, we have never had the vibration, we have the standard non chrome rims, and have replaced the tires once, neither set caused vibration. the car here is a revelation, smooth fast V8 power, luxury, equipment, its brilliant, and so maybe owners should stop moaning about oil of all things, if the car didn't have an oil indicator you all would not be moaning about it, it would simply require topping up, but as you can see the percentage going down its something to watch! if you can afford an expensive luxury sports saloon, maybe you should just spring for some oil from time to time, come on, the engine is being well looked after by the oil, so just top it up, is it a huge problem? No, it is not, just enjoy your car. There is no problem with the engine, its brilliant, no German engine is as nice. It's a Cadillac, the Standard of the World, just give it oil!!

22nd Apr 2004, 11:46

I own a 1999 Seville SLS with about 70,000 miles. I purchased it used from the dealer in 2002. It ran great, with no significant problems other than the oil consumption of about a quart or two between oil changes. The service department told me that this was normal for the northstar motor.

About 6 months later, the car started to die upon de-acceleration, usually on a slow right turn. It would happen about once or twice a week, very sporadic. I took it in for service several times, but they couldn't get the car to die during the test drive. They finally called the head office, and they said it was the EGR system, so they cleaned it out for about $400 (not covered by my extended service agreement). It seemed to work better for about a couple of months, but the problem returned. The service department claimed they could not diagnose the problem because they could not get it to die on test drives. Upon my request, they finally hooked up a monitor to the car's computer, and I had to press a button when the car died. I took a couple of readings and returned the monitor, but still no answers. It's very hard to control a car that dies on a turn with no power steering. I wanted to turn the car in and purchase another one, but the dealer won't take it until the problem is resolved. My only alternative is to change the EGR system, which is very costly, and "is not covered by my service agreement", and they cannot guarantee that it will fix the problem.

I am also having trouble with my cruise control. At 70 mph, the car's speedometer begins to fluctuate. You can feel the car hesitating as the speed goes up and down from about 63 to 70, while the cruise control is on. Eventually, the cruise control stopped working. The car is in the shop right now, for two days to "tear it apart, to satisfy the service agreement", is what the service manager said.

Last, but not least is a leaky trunk. Rain is somehow getting into my trunk and accumulating in the spare tire bin. They are also addressing this problem right now. They said it would cost about $100 to diagnose the problem, and anywhere up to $500+ to fix it.

I love the power, comfort and beauty of the car, but the problems out way the luxuries, especially dying on turns. I've come close to crashing the car many times. Has anyone else experienced this similar problem?


9th May 2004, 12:46

My wife and I purchased a used 1999 STS less than 2 months ago. It had 76,000 miles on it, so we thought we better buy the extended warranty offered by our dealer. This added another $3,000.00 to the bill. After owning the car for 1 month, I noticed the temp gauge running up close to HOT. I checked the radiator and noticed it was a bit low and added water. The problem continued, so I took the car into our local dealer. They informed me, after running some test, that there was a problem with either the head gasket or the bolt holes in the block. I guess water and oil are merging. Anyway, they talked to the warranty people and the cost will only be covered IF it's a gasket problem. (I'm finding out there are some problems with bolt holes in this particular aluminum block.) I guess I missed that part of the fine print when we purchased the warranty. We thought it would cover pretty much whatever happened. Silly us. So has anyone else experienced this problem or know of someone that has? If so, please contact me. I'm going to fight this if I have to picket my local Cadillac dealer. Wanna join me?

Steve Drake



29th Jun 2004, 17:34

Paul, What is the SEA FOAM you mention? As long as I'm asking, what is Marvel Mystery Oil? Thanks!


29th Jun 2004, 19:23


Thank you for your advice. I did get the water leak in the trunk fixed, after the service department charged me a $114.00 to "test" the leak and they still weren't exactly sure what the cause was. I went to the the body shop and asked them to replace the seal for about $60, and tested it myself, free of cost by "feeling if it was wet after it rained".

I will try the SEA FOAM and Marvel Mystery oil and eventually work my way to fixing the vibration in the tires, which is minor to the problem of my car dying upon de-acceleration.

I really appreciate your advice... thanks a million!