A 1980s Rolls Royce Silver Spur should do the trick. In addition to extraordinary comfort, it is a work of art. Check out the exquisite seating and wood appointments in this example:
You can get one of these for $20,000 to $30,000.
Wellll, try a Lexus LS400 for a creampuff ride and rock solid reliability. Sorta like being between “a rock and a soft place.” For example, we own a 1990 (first year) LS400
now with 230,000 miles and it has all original: suspension, exhaust system, starter, alternator, fuel pump, window motors, switches, seat motors… you know all the stuff that usually needs to be replaced a couple of times or more in 230K miles. Rides like a cloud. Engine and transmission seem like new, as does the paint and leather. Our good condition 1990 is proably worth $2,500, so that is about the least expensive range of cost, and of course you could get up to the low $20’s with a 2000 model.
Other nice things: big trunk, big sunroof, very comfortable seats front an rear, real wood trim (our looks like new), and about 22MPG + highway (better on the newer LS models).
That is a very subjective question but by far the most comfortable car I’ve ever owned or driven is my Lincoln Mark VIII. Great ride, handling, and seat design.
I’ve had 2 lower back surgeries and one neck surgery and with most cars on an extended trip a 150-200 mile stop is a necessity for me.
With the Mark I’ve driven for extended distances without even a pause. I’ve made several trips from my home to Ft. Hood, TX (425 miles one-way) with not even one brief pause on the trip and have experienced no problems at all.
When I wanted to improve the ride of my 1965 Rambler, I would go out and drive my 1950 Chevrolet 1 ton pick-up truck. The Rambler then seemed like the smoothest ride in the world. To improve the ride in my 1 ton Chevrolet pick-up, I would go mow a field with the Farmall F-12 tractor. This made the pick-up ride like a dream.
In other words, ride is subjective. I played a concert a couple of weeks ago and two of my passengers commented on how comfortably my 2006 Chevrolet Uplander van rode and how comfortable the seats were. One of my passengers drives a Cadillac DeVille and the other a Buick Park Avenue. Why did they think my Uplander was so comfortable? We had been playing for 2 hours in the most uncomfortable chairs that I have ever sat in.
Yes, I used to love my beat up old Corvair after I drove the company Greenbriar.
i’ve been partial to older mercedes - mid 80’s 126 chasis especially with lumbar support. the rear power seat options were very nice to made me want to have the kids drive so i could sit in the back. also 92-93 e420’s very very comfy but too many other issues with the car. the mb’s were very comfy and handled well and even cornered respectively. lincolns, caddies and buicks have the mushey driving your living room around feel, if you stay away from the “sport” ones. some otheres to try - lexus, infinity, jaguar. generally the bigger the car in these cars the smoother the ride. good luck.
I had an 87 Ford LTD. It had many, many issues, but an extremely smooth ride and not too bad handling for such a large car. The suspensions on these were very durable as well.
Besides the 7-piston pump, the Citroen hydraulic system had two pressure accumulators, one of which was exclusively used for the braking system, so in case of a major leak or pump failure, the accumulator would provide emergency braking power. I own a '73 Citroen SM with the Maserati V6 motor…it is by far the smoothest, most comfortable-riding automobile I have ever driven…and the car still gets over 20 mpg because of its magnificent aerodynamics and low-drag coefficient. Very expensive to own but very, very satisfying. Almost like it as much as my Subaru Justy 
now there’s a combination for you!
I’m surprised by some of the answers here and what people feel is a soft smooth ride. Town Cars and Crown Vics really aren’t that smooth at all relative to most modern vehicles. As someone that used to work for BMW I can tell you to cross it off the list unless you like “sport comfort”, as they’re not tuned to soak bumps up so much as maintain composure over them.
It’s pretty much universally agreed on amongst automotive journalists, and most folks who’ve worked at dealers and who spend time in many cars, that the 1990-1999 Lexus LS400/LS430 is the gold standard for a soft smooth ride and whisper quiet interior. Not only that they’re some of the most reliable and durable cars ever crafted. If you want pre-2000 luxury there is nothing in the world (yes not even Rolls Royce back then) that compares to a Lexus LS for silence and smoothness.
Don’t listen to all these idiots suggesting a damned Rolls Royce…imagine fixing something on that. It’d cost you more than it’s worth. You don’t need a Lincoln, either. Try a mid to late 90’s Olds 88/LSS, Pontiac Bonneville, or a Buick LaSabre. You’ll get one for $2500 to $5000…some can be had with a supercharger (for 230-250hp), and, in the case of the Olds LSS, have superb handling and ride qualities.
You just don’t understand, scotty. This is a dream sequence; it isn’t real. If your dream car is am Olds 88, that’s just fine. I’ll wonder about you, but it’s OK to have a dream car of any sort. Hey, some lunatics dream about a Citroen 2CV! Talk about stark, raving mad!
Really there’s a lot of factors in ride quality, but probably the best are how far the passenger compartment are from the wheels. No matter how high-tech the suspension is, you can’t beat distance for isolation. As I mentioned in a previous post, the LTD I had, had very good ride quality. It was pretty much unflappable over about anything you could throw at it, while not being as ‘unsettled’ as some Buicks I’ve driven over rough roads. I like my current LHS because the ride quality is OK, though not spectacular, but it’s a good trade off balancing handling and ride quality. If someone says LTDs and Crown Vics aren’t so good in ride quality, it sounds like someone that’s never driven one. I’m not much of a Ford fan, but I’d have to say that my LTD could probably drive through a minefield and not spill your coffee. I’ve driven a LS400, and while it’s a far better handling car than my LTD ever was, it certainly didn’t ride as well by any means. If I was driving the trip, I’d probably choose the Lexus, but if I had to be a passenger or to sleep in the backseat, I’d pick the Ford anytime. But over both, I’d choose my current car, as the Lexuses (Lexii?) and Toyota Avalons I’ve driven have a lot more torque steer than I like, far offsetting any slight advantage in performance/ride. And they seem a lot more flaky over wet curves than my well-known Chrysler, though it may be a tire issue.
As stated before; you can get use to the ride of many cars with good seating. That would be a primary concern. Also, like boats, longer wheel base helps if the suspension is right. My personal favorite has always been a Crown Vic with HD suspension as handling is as much part of a good ride.
The new 4 Runners are reasonable turnpiker’s and handle deep ruts/potholes etc as well as anything out there; better than a Lexus/Lincoln lux lines. If you travel on rough roads, nothing beats a contemporary mid/full SUV.
Lincolns are smooth, but if the shocks are worn, it can get scary. In those years a Lexus LS400 or (for less $$) and ES300/330 would be very smooth. What $$ do you want to spend?
I have arthritis, and I’ve found (the hard way) that I have to have a smooth ride. However, I’m going to be looking for newer cars. But, that being said, my Buick Riviera 1989 was such a smooth ride. I could drive for hours in that with no problem. Now in my eco-friendly car I can barely go anywhere. Will be looking for another car later on, and am reading your postings with interest. Good luck! Happy hunting!