2010 Cadillac DTS 4.6 Liter Northstar
Summary:
Definition of Class from a Bygone Era
Faults:
Shortly after acquisition, I chose to perform catch-up maintenance, such as having the cooling system flushed and air filter changed, although I wouldn't consider these repairs. I did have to have both front struts replaced, as one of the bearing plates was broken.
General Comments:
I unexpectedly inherited this vehicle from my father, who was of the generation that venerated Cadillac and considered them to epitomize class and success. The 2010 DTS is certainly one of the last of the full sized sedans, and while it would not have been my first choice of cars to purchase for myself, I find it has grown on me. In fact, I had already bought a new 2017 Ford Explorer 1 1/2 years before the DTS came into my hands, so obviously opted for quite a different kind of vehicle.
My father bought this car used in 2012 with about 25,000 miles on it. I've only owned it for six months, acquiring it at around 68,000 miles. I remember driving it home for him and thinking it would never look that good again. He was not big on maintenance, and unfortunately later hired some people of ill repute who had access to the car and basically ran it into the ground. And being an old man, he had a habit of sideswiping things with his big Cadillac before he lost his license, an unfortunate stereotype that seems to have a large degree of merit. So, I acquired an 8-year-old Cadillac with a number of paint chips, a dirty interior, and an uncertain maintenance history. It was much like the old Disney cartoon of the once-happy car that had fallen on hard times, passing through the hands of worse and worse ne'er do wells, until it found someone to rescue it. In fact, I came very close to simply giving this car to an uncle, but I have a history of snatching vehicles out of the jaws of the junkyard demons (note 1964 Dodge 440, 1967 Chrysler Newport, 1973 Dodge Charger), and I felt some compulsion to restore a bit of dignity to this Cadillac. Although my generation doesn't consider Cadillac to be the gold standard as it once was, I believe there is nothing sadder than a former luxury car that has been neglected and not cared for, and allowed to fall into decline. Unfortunately, you see them all the time--dented old Cadillacs driven by guys with grease rubbed on their bellies protruding through open, flapping shirts; bums who think the mere fact of driving an old Cadillac, albeit with 170,000 miles with all the warning lights on, imparts some degree of class that they will never attain on their own. I did not want that to be the fate of this car.
So, I began with some catch-up maintenance. In order to establish a baseline, I went to a dealership and had them do everything that would have been included up to the 70,000 mile service. That essentially meant checking things, oil change, replacing the air filter and wiper blades, and thankfully no other problems except the following. I had to have both front struts replaced--probably from somebody not caring that they hit one pothole too many time, because what the heck, it was somebody else's car. I also had the cooling system flushed, though it was before the recommended mileage, because I have heard of the warping heads on Northstar engines and hoped to avoid that with a clean and efficient cooling system. The cooling system flush was about $300, and the front strut replacement was $1,600. After that I moved on to touching up all the little paint chips, and re-affixing the front fog lamp assembly, broken probably by my dad going into the ditch once too often. After detailing the interior and hand waxing, it appeared that I had a pretty nice looking car. That's the other thing: one should be so ashamed at the idea of allowing one of these old full-sized Cadillacs to leave the garage dirty, that it will never be allowed to happen. That's a rule.
From the driver's point of view, my 2017 Explorer is quieter and rides better. However, from a passenger's point of view, my wife finds the big leather seats in the Cadillac more comfortable than the Explorer. And my father-in-law, who has religiously driven only Honda Accords since the 1980s, proclaimed after his first ride in this or any other Cadillac that he had just had an epiphany--he never wanted to ride in any car other than a Cadillac again. So, even at 9 years old and over 70,000 miles, it's not bad and better than many. It is pleasant to drive, although I feel that the car does not insulate one from road noise and bumps as one might expect from a luxury car. This could be the fault of an abused suspension, however, and might not apply to one taken care of in a better manner.
It is also my impression that one needs to step on the gas a bit more to maintain speed, despite the V-8. When not paying particular attention to the speedometer, I find myself going a few miles under the speed limit. By comparison, in my Explorer with the turbocharged 4-cylinder, it's easy to find myself speeding and you don't even feel it. I thought I was doing 55, but actually doing 70. Oops! In a strange quirk, I have learned to avoid taking the car through an aggressive undercarriage wash, because the water jets seemed to affect a series of sensors. My first time through the full wash, the check engine light came on and stayed on until the next day when the wiring dried out, though this has not happened during driving in the rain. In another instance, I started the car and it ran rough and choppy, with several warning lights coming on for a few minutes--never happened before and never happened since; just weird. I chalked it up to thinking it just needed to be driven consistently.
Again, despite the V-8, gas mileage is quite good. In mixed driving, around town with some 50-mile highway runs, the car returns 19-20 mpg. However, doing 65 mph on the highway for several hours returns about 26-27 mpg, which I thought was pretty phenomenal for a large V-8 sedan.
So, the car has grown on me, and I think I have restored its dignity. I take care of things so they last, and expect to get several years of use out of this DTS, providing it does its part. I'm aware that the Northstar engine has a certain reputation, and the late 2000s were not the high point of General Motors quality, but I'd like to see if my maintenance and usage habits will carry the day, although at current mileage, it will take five years to even reach 100,000 miles. It has become the vacation driving car to keep miles off the Explorer, and has also become the weekend car if the weather is bad, to save the '73 Charger and '71 Barracuda, both of which it rides far better than, by the way.
Would you buy another car from this manufacturer? Don't Know
Review Date: 23rd April, 2019
22nd Mar 2020, 13:48
This is the original author posting an approximate 1-year update to my review. Since my last update on April 23, 2019, I have put 9,050 miles on the car and mileage stands today at 81,050. After owning the car for about 1 1/2 years and putting nearly 14,000 miles on it, I think I would add a subtitle to my original single phrase that is supposed to describe the whole car: "Ain't no such thing as a free lunch!" Although I inherited this car with relatively low miles, that has not translated into repair-free use. It also illustrates that there are time-dependent failures that can occur on a car with relatively low miles. Let me explain below.
Upon acquisition, I had the cooling system flushed out in hopes of prolonging the life of the water pump and avoiding the head gasket leaks I've heard about on Northstar engines. I was too late for preventative maintenance to have an effect, unfortunately. The water pump needed to be replaced at 77,400 miles at a cost of $1,100. This led me to review Northstar engine cooling systems. There are some sources, including a mechanic that I usually trust, who recommend replacing the orange Dexcool with regular green anti-freeze, thinking the orange Dexcool is the problem and that it corrodes the aluminum head and allows head gaskets to fail. However, my reading convinced me that the orange Dexcool is the correct coolant for the aluminum engine block/heads, but that it does not last the lifetime/100,000 miles that GM engineers intended. By the time I had the coolant flushed, it was already too late to save the water pump. So, I will stick with the orange Dexcool, but recognize that it needs to be flushed out every three years. I also believe the head bolt issue on the Northstar was fixed by 2010, but anytime you have aluminum heads, maintaining the cooling system is a must.
With the water pump behind me, my problems were not over. At 79,635 miles the fuel pump died. Luckily, these things all happen at home. The fuel pump could easily have stranded us on the highway some where, but I had no idea there was a problem until the next time I tried to start the car in the garage. And that means, when the fuel pump seizes up and continues to draw current, it burns out the fuel pump relay, which means the entire fuse block under the back seat has to be replaced. There went another $1,400, although a very small portion of that cost went to pre-emptively cleaning the fuel injection system.
So let's just reiterate: front struts, water pump, and fuel pump all before 80,000 miles. I suppose one could argue those failures occurred after 9-10 years on a car that until I got it had sat outside or in an unheated garage, which could have taken a toll. However, to me they seem like premature failures. Throw in a couple of oil changes and the coolant flush, and I have $4,300 in this "free" car after 1 1/2 years of ownership. That averages out to about $220/month or 31 cents per mile. By way of comparison, that is still 1/5th the monthly cost and 1/3rd the cost per mile of my 2017 Explorer, which I paid cash for about two years ago and will continue to average out over the coming years. However, it's double the monthly cost and triple the cost per mile of my 2002 Explorer; it's four times the monthly and per mile costs of my old Dodge Ramcharger, to offer some comparison. So, still cheaper than buying a new car, but right now a lot worse than other used cars I've owned. This Cadillac really needs a few tens of thousands of repair-free miles to bring those averages down. Just yesterday, the "Service Tire Pressure Monitoring System" warning came on, so the prospects of trouble-free driving are not great. That one I'm going to ignore until I need tires or have some other preventative maintenance done - I plan to get the transmission fluid, brake fluid, and power steering fluid changed within the next year or so.
I see it may be a challenge, but I'm determined to see this car reach 150,000 miles. That is a sad goal of underachievement and tells you how much faith I have in the car, when my Ramcharger went to 260,000 miles and my 2002 Explorer went to 207,000 miles (and I know I could have kept it going much longer). When I bought my 2017 Ford Explorer, I basically gave my old 2002 Explorer to the dealer in trade thinking at least I would not have to keep paying to fix stuff on it. And yet, here I am. The Cadillac DTS really has grown on me, and we use it for driving vacations and cross country trips because it is comfortable and because I want to give it the opportunity to earn its keep. We just went on a trip to Tennessee, and gas mileage was 24 mpg in the hills and 26 mpg with interstate driving, which does impress me for a full-sized, V-8 sedan. By the way, I used manual calculation to check the trip computer, and they match to within the tenths decimal place. Some people don't seem to believe that a large V-8 sedan can get that kind of mileage and assume they must be "instantaneous mileage" numbers. And if I'm putting 10,000 miles a year on it, it is saving wear and tear on my new Explorer. However, with this spate of expensive repairs that I consider premature, I would have to say that even though I am thankful that I can afford to absorb these costs (though not with a smile, you may believe) and I'm getting use out of the car, I would recommend that if an average working guy is considering putting on airs by driving an old Cadillac, they had better reconsider because it will bleed you. So, I'm going to continue taking care of the car and maintaining it as is my nature, and I'm going to keep driving it until it has a "permanent fatal error" and give it the chance to bring the average costs down. I know the tone of this update is on the negative side. It's a nice car and I like it, but I wouldn't have bought it used and if I'd known it was going to cost me what it has in such a short time, I might have more seriously considered just giving it to that uncle. Though he would never have spoken to me again.