"It's not your father's Oldsmobile!"

So goes one of the year's more ingenious sales pitches, obviously aimed at aging baby boomers like me, graying at the temples but still wearing blue jeans and squirming under the mantle of maturity. Nowadays we have our houses and our lots, our 30-year mortgages, children, crab grass, golf clubs and insurance portfolios. But just look beneath the surface and you'll find a closet hippie who still yearns to tune in, turn on, drop out and hit the road in a parti-colored Volkswagen van.In my case, the schism is doubly troubling because I already have an Oldsmobile. Not the newfangled version with European styling, electronic ignition and displacement measured in liters - but an old-fangled all-American gas hog V-8 Cutlass manufactured in 1968. It is, in fact, the kind of car my father might have driven.

Twenty years haven't dimmed the memory of how I came to own an Oldsmobile - and no, it didn't have a blessed thing to do with politics or social standing. It was just plain love at first sight.

In 1968 I was what might be described as a footloose vagabond, one of many young people caught up in the idealism and restlessness of the time. Inspired by lyrics of a Simon & Garfunkel ballad, I had packed my guitar and set out via Greyhound bus to "look for America."

One day while drifting through the Southwest, I ran across a girl I had known briefly before in the Peace Corps. Anne was a graduate student at the University of Texas, and like me, she owned a guitar and had mastered the four basic chords of "Blowin' in the Wind." She dressed in the manner of Joan Baez and had her own off-campus apartment in Austin that was tastefully decorated with protest posters and candleholders fashioned from old wine bottles. The only incongruous element in the picture was her wheels - a brand new 1968 Oldsmobile!

Everything went swimmingly between us except whenever it came time to go somewhere. One night I remember we were driving to a Buffy Saint-Marie concert and I finally asked her, "What's a hip chick like you driving an Establishment type car like this?"

Anne's explanation spilled out in the form of an apology. "It was my daddy's idea," she began remorsefully.

She went on to say that what she'd really wanted was a cherry-red Triumph Spitfire. But her parents were dead set against the idea, arguing that in any collision on the streets of Dallas (where General Motors reigned supreme) a foreign compact would fare no better than a Lone Star beer can. As a matter of fact, import squashing was something of a popular sport in the fast lane of the LBJ Freeway - no doubt a prelude to the contemporary practice of Japanese bashing.

By way of compromise, Anne's father had taken her to Leon McNatt's in Denton and permitted her to pick out the "smallest" Oldsmobile in the showroom.

So it came to pass that we two hippies set out on life's road together in a car that was practically a symbol of bourgeois smugness, at a time when many of our ilk were actively engaged in overturning such symbols, sometimes setting fire to them.

All across the nation a new generation was growing hair and trading in the accoutrements of affluence for beads and trinkets. From the suburbs of Dallas they fled to dusty communes in New Mexico, where they became potters, weavers, poets and poor farmers. It was something that had never happened before in the history of civilization - the revolt of the middle class.

Caught up in the spirit of downward mobility, Anne and I packed our meager belongings and headed for San Francisco, where we hoped to be assimilated into the unwashed community of hippiedom that had sprung up in the vicinity of Haight and Ashbury streets. Along the way we saw hundreds of ragged young vagabonds standing beside the road, their thumbs pointed in the same direction. As our Oldsmobile hove into sight their thumbs automatically dropped; peace signs gave way to other gestures, less friendly, as we passed in air-conditioned comfort.

Nor were we exactly welcomed with opened arms when we arrived at the city by the bay; that is, except for uniformed doormen who rushed to assist us whenever we parked in front of a fancy hotel.

"No thanks," we explained. "We're hippies. We're just looking for a place to roll out our sleeping bags and crash."

All up and down the coast of Northern California we searched for such a spot, but whenever we stopped the reception was the same. Hostile bearded faces pressed menacingly against the windows; disparaging remarks were made regarding our car, Texas, General Motors, Leon McNatt and the military industrial complex. Luckily we had the edge in horsepower, and thus managed to escape San Francisco unstoned. Discouraged, we split the scene and hightailed it back to the heartland.

Time marched on; the seasons changed. We grew older, found jobs, and by degrees were assimilated into the middle class from which we had fled. We bought furniture, a house and became credit card-carrying members of the dinette set.

The years rolled on like numbers on the odometer. When the car reached the 50,000 mile mark, we paused to celebrate with a roadside ceremony. Years later, when the odometer reached 100,000, I was somewhere between home and a grocery store and didn't bother to stop. When the car passed the 150,000 mile marker, I forgot to notice.

People who keep the same car forever come to regard it in human terms. Anthromorphologically speaking, a vehicle that's gone 100,000 miles is thought of as a doddering centenarian. One that's been around for 160,000, as ours has, is like one of those miraculously long-lived Russian villagers one reads about in National Geographic Magazine. Our friends wonder if it isn't due for an overhaul, or some automotive equivalent of quadruple-bypass surgery. But my mechanic assures me it doesn't need an operation; it doesn't smoke, and thus can be reasonably expected to live on to an even riper old age.

Oh sure, it leaks a bit, leaving little puddles of transmission fluid here and there - but then incontinence is a normal symptom of the aging process. Now and then a pump goes out or a bushing gets bushed, but if you're not making payments you can afford to fix a car.

Accidental death is something else again, and over the 20 years since it rolled out of Leon McNatt's showroom, our Oldsmobile has had some brushes with disaster. Two or three fender benders, but the worst was when it was sideswiped by a Kenworth truck and "totaled," according to the insurance report. But we used the settlement to put her back together, scavenging parts from auto graveyards in the manner of Dr. Frankenstein.

Lately she's fallen victim to the insidious affliction of rust, but after several operations we're hoping the cancerous disease is in remission. One positive side effect is that our car now contains so much plastic body filler that it can glide through radar traps undetected. The world's first stealth Oldsmobile.

Over the course of two decades the car has won my grudging admiration, and now they tell me that muscle cars of the '60s are making a comeback. If so, it'll be the first time in 20 years heads have turned in admiration as I sail past behind the wheel of my father-in-law's idea of a swell car. I guess in retrospect he wasn't such an old fuddy duddy after all. Just ahead of my time.