I have a 1990 749 turbo wagon which was purchased practically new with only 60000 miles at that time. She has been with my family till now with 300.000 miles driven with same engine and tranny. My question is how much can we expect of her going forward? Have we driven the life out of her? Is it time to purchase something newer?

749? Must be a wagon based on a 4-doors-each-side Limo body....chuckle.

With care/feeding, it can accumulate an almost unlimited number of miles. Irv Gordon's still driving his '66 P1800 -- now 3+ MILLION miles.

It's up to you.

If it’s still performing it’s duties reliably and doesn’t cost a lot of money or time to keep it going, I would keep on driving it.
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Current rides: 2005 Volvo S80 2.5T, 2003 Volvo V70 2.4NA, 1973 Volvo 1800ES (getting ever closer to road worthiness)

As you know, the 2, 7 and 9 series Volvos can run 300k, 400k and even 500k+...

If you still enjoy it, it runs well and you continue to maintain it there is no reason not to keep driving it. It really is a subjective decision. OTOH - At 300k I sold my 90 240DL. The plethora of issues and questionable reliability really started to wear on me so I choose to move on.

We had our '90 744 TI up to 250K miles - our daughter brought back her '96 854 because she leased a new car.

So we tried to sell what was a fast and beautiful black sedan.

I couldn't give the car away!

I would try to sell your car, if you cannot get a fair price, then drive it until it needs an expensive repair and then give it away to a budding mechanic.

I could not get a decent offer for a beautiful Fire Red '96 855R when it was 17 years old and a fast car.

I traded it foe $1000 - the sales manager told me that they would auction it - I told him to drive it and boot it on the highway - they kept it on the lot for 6 weeks, then its new owner gave me a call.