The Department of Buildings and Grounds (B&G) will replace its fleet of four shuttle buses by next year and solicit bids for a new bus next week.

Carl V. Swanson, superintendent of central services for B&G and responsible for overseeing the shuttle bus program, said yesterday the current buses are five years old and experiencing some mechanical problems. "They don't hold up the way they used to," he added.

Swanson said B&G will purchase one bus within the next few months and probably order three identical models next year if the performance of the trial bus proves satisfactory. He said the new bus would probably seat 20 passengers, like the buses used currently.

Joseph N. Tremml, vice-president of Transport Engineering Co., which sold the four buses to Harvard in 1974, said yesterday the buses should last for ten years if used twice daily like most schoolbuses. "I don't know of anybody in the nation who uses that bus as much as Harvard does," he said.

B&G administrators agreed the Harvard buses have worn out quickly. Anne M. Gregory, shuttle bus coordinator for B&G, said yesterday the Harvard buses drive an average of ten hours per day and now log at least 60,000 miles each.

"Picture driving 60,000 miles in Harvard Square traffic and you've got an old bus," she added.

Gregory said B&G could not purchase buses larger than the current ones because of the narrowness of the shuttle bus route at certain points.

J. Lawrence Joyce, director of B&G, yesterday said B&G is waiting to see if the Working Committee on the Handicapped Program at Harvard recommends the purchase of shuttle buses equipped with hydraulic lifts before the new bus is ordered.

B&G currently operates a van that accommodates two wheelchairs.

The committee drafted a memorandum yesterday recommending that B&G purchase a second van for disabled persons instead of shuttle buses with lifts. Nancy E. Randolph, special assistant to President Bok and coordinator of the committee, said yesterday.

Randolph said the committee prefers using vans because they provide door to door service and are not so crowded as the shuttle buses. She said a second van would provide back-up service and could cover such additional areas as the medical school.

Karlo F. Duvnjak '80, a shuttle bus driver, said yesterday he hoped the new buses would be more compact. "I'd like to drive a new bus," he added.

If it purchases the same model it bought five years ago, B&G will have to pay much more money, Tremml said yesterday. The model that sold for $7800 in 1974 now sells for about $15,500, he added