I used to.

Then I changed driving position and kept moving my arms around every 10 minutes or so..Problem disappeared.

The Swedes (I say Swedes because I'd include Saab in this) have always been ahead of the game when it comes to orthapeadic seats. I am driving a Land Rover Discovery 2. It has rake but no reach adjustment. Thankfully I have solved the issue by combination of moving seat further forward and lowering the steering wheel.

I have always driven Land Rovers and quite possibly because of that I find other cars very uncomfortable to drive in general, not just the seats. As a result I won't be swapping anytime soon.

I'd suggest that anyone uncomfortable enough to think about changing cars should have a Volvo on their shortlist. The seats are some of the best in the business, and as far as I know the steering wheel can be moved both up and down and fore and aft on all models.

When the Fiat Punto first appeared (1990s?) many people, including HJ, said it had excellent 'orthopedically-designed' seats. I had one for a year or two and found them comfortable.

Problem is, every new model has to have completely redesigned seats (why?). Like everything else in present-day cars, styling trumps all. My Pug is being fixed as we speak, and the fixer says that he can't understand whether the needs of assembly or re-assembly were ever considered alongside the overall appearance. Part of the reason why repair costs so often make relatively minor accidents into write-offs.

Anyone else suffer from stiff/achey shoulders whilst driving?

Yes. I suspect lots of other OAPs do, too.

solutions anyone?

Armrests.

The only things that stop your arm falling off are the muscles and ligaments around the ball and socket shoulder joint which is so shallow there is nothing else to stop the ball of the arm bone falling out of the socket of the shoulder bone. Constant tension on these tissues can be painful.

I cannot understand why car seats are not equipped with adjustable arm rests on both sides like the van I drove the other week, especially when so many hours are spent sat in jams.

As an OAP with moderate osteo-arthritis, it's all down to the correct seating position which either requires lots of different adjustments or a lot of luck - but that's no different for the young, fit (original definition) whipper-snappers.

I've always taken my time in car showrooms, getting the seat/steering best suited for my comfort - often having to ask salesmen to b****r off and leave me to it - and then having optimised the driver's seat position I then get into the back seat behind it to assess the comfort for a passenger my size.

I don't think that arm-rests are meant for use while driving, I doubt that any safety organisation would endorse their use - how ever much it's shown in American films.

Going off-topic slightly, John F's observations about the shoulder joint reminded me of having a carpal tunnel operation on my right wrist and needing to minimise the use of that arm for a week or so. I bought a "spinner" to attach to the steering wheel, so that I could steer mainly with the left hand (my car is an automatic, so I didn't need to use a gear lever whilst on the move). Using the spinner caused a recurrence of pain in my left shoulder, which I used to get driving vans and minibuses with gear levers which were very stiff to operate. The recurrence led me to conclude that spinning a steering wheel under the palm, which lots of drivers do, is really bad for the shoulder joints.