2nd Aug 2004, 07:59

"There's no oil hole in the piston"

(for the oil scraped by the oil piston ring to allow the oil to drain back down to the bottom of the crankcase)


This answer was revealed to me during a conversation last week.

Evidently, most 4 cycle car engines have (for a long time) had a 'oil hole' in the pistons. That's why my old 350 cu in engines never burned any/much oil between changes.

That's why GM says its "normal" for a Northstar to burn oil. Now, as to why Cadillac would alter a design like so is a question for Cadillac/GM.

8th Aug 2004, 10:29

I recently purchased a 1999 STS with 58,000 miles. Lately I've noticed what I think is a slight tappet noise along with a corresponding mis noticable at idle. I changed the oil and noticed that it was very thick and sticky, but not dirty. There was only 3,000 miles on the oil. The oil had been changed from the Cadi dealer when I bought the car. I installed a new filter and 10/30 oil and now the tappet noise is really loud and the idle much more bumpy. I think the dealer put 50 weight oil along with an additive to hide the problem and waited for a sucker like me to buy the car. Anyone else with the lifter noise? Rich.

19th Oct 2004, 14:35

I have an '01 Seville with 58,000. It developed a cold engine lifter noise that went away after the car warmed up. The dealer claimed it was due to carbon build up and did an "injection process" to clean the upper chamber and injectors. It's better, but not completely gone.

For those of you with high speed vibration, I too experienced that. I changed to Michelin's from factory Goodyear's. No help. The car came with factory chrome rims. The dealer replaced with different style chrome rims and the problem went away immediately. The car rides like a Caddy should.

16th Apr 2005, 09:07

I bought A 99 De ville De Elegance about 6 Months ago. I loved the car. I still love the look and the comfort of the car. At about 120,000 miles I got a low oil warning followed by an overheating warning. I immediately stopped the car and called a service truck. After replacing coolant and oil I was on my. A couple of days went by with no problems. Then the car would overheat when pulling small hills or after driving more than 70 miles. My dealer has informed me that the head bolts are pulled and it will be $3000 to repair the problem, but there is no guarantee that it will fix the problem so what I should do is replace the engine and that will be between $6000-65000. I will have to sacrifice the comfort and style of this car for a company that will stand behind the engine that they put into the product they sale.

4th Jul 2007, 12:17

I have a 1999 Cadillac STS siting in my drive way with a blown engine! Wife was 1 mile from the house when the car died. towed it home, removed intake and discovered a hole in the intake well under the internal stater. The number 5 connecting rod broke and when it come back around pushed up through the bottom of intake well. It I feel didn't have that many miles on it to do this. Contacted Cadillac, said to take it in to a cadi mechanic and if they felt that it was a defect that they would HELP with the repair. Like any cadi mechanic is going to say it's a manufacturer defect, so here I sit with payments on a car that I can't drive. And I don't want to spend more money than I want to on something that's not going to be worth what I have in it! Bought a Honda...

27th Jan 2011, 10:43

I bought a '99 Seville STS with 103k on it.

It had blown its head gasket by 107k. Got the whole engine rebuilt for $4500.

I love the car, well worth it. Nothing compares to the ride enjoyment of this car. I decided to go this route because there's no options that compare to the Seville under $10k.

16th May 2011, 19:33

I had a 94 STS, and now have a 00 STS, and both cars had an issue with oil leaks, not consumption. It's ridiculous that GM knew this for so long and never corrected it. It's the only problem with the car; otherwise it's the best all around sedan to own; matches and surpasses any foreign car of its class.

7th May 2012, 11:02

Have your front motor mount checked. I just had a 1999 Cadillac STS that had the same problem. The mount was the problem.