Faults:

Absolutely nothing. It has run on fuel, oil & filters for 40,000kms since I've owned it!!!

General Comments:

Advantages:

Excellent long and longer distance vehicle. Thought it would let me down on a 8000km road trip across Europe, when the check - engine light came up and on the last 500km to home it started to "rattle" in the engine-room and the screening said Error??? (don't remember). Mechanic said on the phone this could result in a 7000.- Swiss Francs (16 hours of work to change the timing-chain, at 120.- CHF per hour) repair. Thank god, I only had to add a liter of oil. Check engine light disappeared (deleted it). The rattling too. PFFFFFFF!!

What I really like is:

Up to speeds of 200km/h one feels like you're a living room and totally safe like Mamma's womb, listening to the superb Bose sound system. The only things to be heard are the wind and a tiny bit of engine noise. Above these speeds the 3.6L engine has to work to hard and becomes vociferous at or above about 5000RPM.

The gas / mileage rate is great on highways. 10 liters at 140km/h (85mph) for 100km (65 miles) distance at constant speed.

When I was looking to buy it, I was also looking at a Merc E-350 and BMW 535, which are at least up to me the direct competition of the STS by then (2006). In Switzerland they all had double the price tag with same engine size back then with around about 60k km on the clock. Which leads me to...

Disadvantages:

Very low resale value up to impossible resale, as Cadillacs are not very common cars in Europe. Furthermore, lots of people have got burned into their brain that American cars are gas guzzlers, which they where indeed in the 60s and 70s, but which is totally untrue for US-cars built (way before) after the year 2000. But: "was der Bauer nicht kennt das frisst er nicht!"

For the navigation system there is after 2006 or 2009 no update available, which results in the fact that the system doesn't know entire neighbourhoods/streets and highways built after 2006/2009. Furthermore it is sometimes very much to be interpreted where "she" in fact pretends to lead one.

Flipside of the coin, we always got to our destinations. Sooner or later :))

Use on snow is due to the rear wheel drive... (hate it) terrible to impossible. Which is why on the 4.6 V8 STS you can get it as an 4x4 wheel drive, which I would highly recommend to everyone if living in "snowy" regions.