(FORTUNE Magazine) – IT WAS the highlight of my life,'' says Harwood Cochrane. To get that kind of rating from a 74-year-old multimillionaire, it would have to be a big deal -- and it was. In October the plain-spoken Cochrane, who started with two used trucks in 1935, sold his Richmond-based Overnite Transportation for $1.2 billion, the largest amount ever paid for a trucking company. The buyer: Union Pacific Corp., which will combine Overnite's 4,000 trucks with its trailer- carrying railroad flatcars in a nationwide network. Cochrane will stay on for three years to run Overnite and help oversee the integration of road and rail. Despite his Southern-gentlemanly ways, Cochrane is an autocratic, tightfisted chairman. ''He's very decisive, and no pushover,'' says Andras R. Petery, transportation analyst at Morgan Stanley, which represented Overnite in the Union Pacific deal. Over the years he fought hard and successfully to keep the Teamsters from organizing his drivers. Says William Legg, a trucking analyst at Alex. Brown & Sons in Baltimore: ''Today that is not as big a thing, but when he did it, unions were a rising tide.'' Wages and benefits of $16 an hour, vs. the $21 union rate, give Overnite a competitive edge. It has prospered as the largest non-union company in the less-than-truckload business, in which truckers charge high fees for smaller shipments rather than a flat rate for an entire load. Early on Cochrane learned to keep a close rein on his budget. He left high school at 16 to drive a horse-drawn milk wagon. To pay for the insurance on his first trucks, he borrowed $125 from his wife -- whom he met when she was his cousin's blind date on a 1928 airplane ride. It was nip and tuck at , first; he remembers a load of 400 cases of eggs that froze when Maryland state police stopped him for having inadequate insurance. During World War II, Cochrane multiplied his seven trucks to 31 and stepped out from behind the wheel to run the company full time. Overnite went public in 1957. Recently, deregulation has helped business speed ahead, since Overnite could expand across state lines on its own rather than taking the bumpier road of trying to acquire companies loath to make a non-union alliance. With cash to spare and no debt, fifth-ranked Overnite now serves 34 states and employs 10,400 people; 1985 sales were $470 million. Some of Overnite's charm could be lost in the merger. Cochrane tries to set schedules so drivers can be home with their families at least four nights a week. Tom Donohue, president of the American Trucking Associations, a trade group, warns that if Union Pacific fails to maintain a high-quality work force, ''they will lose some of the asset they bought.'' Says analyst Legg: ''This is a very entrepreneurial business. If you take away the entrepreneur, you risk losing the edge.'' The sale rewarded Cochrane handsomely: Altogether he and his wife, their three children, eight grandchildren, and one great-grandchild came away with $47.6 million. (Cochrane's personal cut was $13.1 million.) He lives on a 1,600-acre spread near Richmond, part of which he has given to the Southern Baptists for a missionary training center. It's within sight of the modest 85- acre farm where he and eight brothers and sisters grew up. For recreation he raises ducks, geese, and ring-necked pheasants, drives 55 miles to Chesapeake Bay when the bluefish are running, and plays a ''sloppy'' game of golf. Cochrane's deal with Union Pacific is the biggest yet in the industry's hammer-to-the-floor rush to consolidate. While haulers with weak balance sheets may simply vanish, other trucking companies will merge, and railroads will continue to forge truck-rail links. ''There will be more of a shakeout in the less-than-truckload business,'' Cochrane predicts. Within three years, he says, six to eight major truck lines could control 85% of everything except short hauls and moving vans. Cochrane won't have to worry about that grimly competitive scenario. Canny as always, he seems to have picked the perfect moment to cash out.