It's raining in Maine at 2:18 a.m., there's snow falling in the Rockies and here beside a bone-dry four-lane north of Richmond "the Big John Trimble Show" is taking a request.

"Whatcha wanna hear, bud?" asks Big John, resplendent in a powder-blue acetate shirt and blowing cigarette smoke out his nose.

The trucking industry's most pupular all-night disc jockey (as voted for the past two years in a poll) is talking on the phone to a trucker getting ready to haul eggs out of Pigeon, Mich. While talking, Big John is cueing up his next record, a cheating number called "Our Love Is More Than Just A Bedroom Thing."

The trucker in Pigeon, who calls himself the "Easter Beagle" and doesn't say why, asks for "Freightliner Fever" by Red Sovine. Big John, his nose still shooting smoke, says, "You got it . . . Here go."

In 32 states, six nights a week, from 11:30 p.m. to 5 a.m., Big John Trimble's flat Kentucky twang rides 50,000 watts of clear-channel radio power to truckers in their rigs and truckers' wives.

Big John, broadcasting on station WRVA-AM (1140) out of a truck stop on Interstate 95 about 70 miles south of Washington, plays country music that deals mostly with the Five D's: divorce, drinking, death, devotion and desperation. "Reality music," Big John calls it. He also reads the weather for listeners between Canada and the Carolinas, Wisconsin and the Atlantic. And Big John tells the truckers they are a fine breed of human being.

In radio parlance, Big John is a "specialty man." He is one of five or six trucking disc jockeys who work for 50,000-watt, long-range radio stations around the country and who compete with each other all night long to get inside the cabs of the nation's trucking industry.

"You get depressed out on the road every night," says Al Selby, 31, a Chicago trucker who listens to Big John when he's driving. "I never feel like I'm gettin' anywhere. But when you call him up, Big John talks to you. Driving down the road, he mentions your name and plays your songs.It brightens you -- gets rid of the humdrum."

The trucking disc jockeys say their job is to play the music and say the words that truckers want to hear. They talk warmly of wives and children, and they play records like "Drive That Rig To Glory," which calls the truckers "a gutsy son of a gun who puts the wheels on American industry."

Big John, like his all-night compatriots in New Orleans, Fort Worth, Chicago and Wheeling, has adopted the same enemies as the trucker -- government regulators, state troopers and the 55-mile-an-hour speed limit.

"You'll never hear me spouting off with that obscenity on the big radio," says Big John, who refuses to say "55" on the air.

From the second floor of Jarrell's Truck Plaza along I-95, just above the "Professional Drivers Only" cafeteria, Big John runs his number-one-ranked-trucking show all by himself.

His studio isn't much. There are two turntables covered with faded red felt and surrounded by stacks of country standards (Great Balls of Fire"). There's a cardboard cutout of Dolly Parton's abundant body and a poster of a sultry red-haired woman in red tights. Below the redhead is a sign that says, "Christ in The World of Trucking."

At 11:30 p.m. just after Garner Ted Armstrong finishes his sermon on religious cosmology, Big John shoves in a tape cassette and the show takes off. "You're listening to the Big John Trimble Show; climb aboard and truck along . . ."

The all-night trucking show got its start 10 years ago in New Orleans when Charlie Douglas, a country music disc jockey, decided to convert his late-night program from a country show aimed at people he knew had to be awake.

"This isn't broadcasting. It's narrow casting," says Douglas of Station WWL in New Orleans. "We point at one guy in one truck going in one direction."

Up until two years ago, according to a poll conducted by Open Road, a trucking magazine, Douglas did a better job of playing cheating music and sympathizing with truckers than anybody else. But in 1978, Big John Trimble, who proudly admits he's never driven a truck in his life, became number one.

Big John, 40, is 6 feet, 2 inches tall with a large, toothy grin. He's married, has three children and, like most disc jockeys, knocked around the country before settling down (in Richmond, which he calls the Big R) two and a half years ago.

His carer in radio started when he was 14 years old in Paintsville, Ky. There, on 250-watt WSIP, John (he wasn't Big John then) played rock and roll music to a population of 450 country folks. "I'd play Little Richard and blow us off the air," Big John remembers.

The day after he was graduated from high school, Trimble hitched a ride out of Paintsville and began 19 years of radio work that took him to seven radio stations across the country. In Seattle, he did an all-night show while suspended 80 feet in the air inside a camper-trailer. The deejay turned from rock to country and, in Spokane, Wash., he turned to the allnight trucking show.

After a brief but miserable stay in Shreveport, La., Big John was called to Virginia by the program director of WRVA who was looking for an allnight alternative to an old-time ballads format. Big John's alternative has worked; the program director loves him.

"Hiring Big John was like hiring a kicking specialist. You don't tell a kicker how to kick, and I don't tell John what music to play," says program director Walt Williams.

The people who tellBig John what to play are his listeners -- truckers who pull off the interstates to call in a request on a toll-free line from a truckstop phone, and wives at home who want to dedicate songs to their husbands on the road.

"Here's 'Movin' On' by Merle Haggard. It's for Champagne Grant, who's running out of Portsmouth, Ohio, to Tennessee tonight. And it's from his better half Bubbles," says Big John, in one of his dedications.

The disc jockey takes calls from regular listeners he's come to know. There's a woman from Pittsburgh who calls herself the "Electric Redhead." For the past tow years she's been calling John to dedicate songs to her boyfriend -- a trucker who calls himself "Roman Hands."

The women who call in the middle of the night are often lonely and bored. They ask for Big John's time and his sympathy. Occasionally, they offer themselves in return. Sometimes they call themselves "Afternoon delight."

"I've never gone out with a listener," says Big John, although he does admit to some spicy conversation off the air. "I never made a date. I just have too much respect for them."

Big John sells truck parts between records ("buy five recon injectors at the regular price and get one free") and insults Washington D.C., as often as possible.

"The winds in Washington are out of the south southeast at 6 mph. Although I don't see how that's possible with all the politicians and hot air there," he says in a weather report.

"I don't know anybody who doesn't like to make jokes about Washington," Big John explains.

After 4 a.m., when the show winds down, Big John picks up the pace of his cigarette smoking, rattles cowbells in front of the microphone to keep the truckers awake and plays a tape recording of a rooster. He's been told that that rooster once woke up a drowsy trucker headed for a bridge abutment.

At the end, just before Brother Mays Johnson solicits donations for the Lord, Big John closes abruptly: "Good night. Good morning. Thanks for the ride. I'm gone."