We bought a 740 wagon a couple weeks ago. After having it checked out, I changed all fluids, p/s, tranny, motor oil & flushed brakes, etc and installed a tranny cooler to help keep the automatic tranny cool.. We went on a trip to Disney World in this car, pulling a very small camping trailer (1,800lbs) . the car drove great, our trip was about 1,900 miles round trip. Most of the time we were driving at about 70 - 75 mph with no problems!. Used NO mortor oil had no leaks. Upon returning home tranny broke the next day. High pitched squealing, delayed shifts, then surging. I've bought a tranny, to install myself today. If your still following this long post, I have two questions:
1). Did we make a mistake using the Volvo to pull the small camping trailer thus causing the tranny failure?

2). Any suggestions / cautions I need to know about before I pull & replace this tranny? Should I use Dextron III fluid or synthetic?

Thanks,
Tony p
Charlotte, NC
90 740 wagon
non-turbo
auto tranny
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