International Buses are actually manufactured by either IC corporation (for International School Buses) or Workhorse (for International RVs). Workhorse supplies the International RV bus chassis. In either case, the parent company is actually Navistar International Buses (formerly International Harvester Buses: IH). Navistar International Buses also manufacture Diesel engines for many different types of vehicles beyond just International buses, including trucks, vans, and SUVs.
Navistar International Buses began (as mentioned) as International Harvester Buses. From 1926 up until about 1979, the progress of IH was stable. They were primarily an Agriculture oriented tractor manufacturer and the did well. They expanded rapidly, which may be the reason that actually led to their brief but brutal restructuring period. As the expanded into other markets, corporate management became somewhat chaotic and the infrastructure of the company began to collapse. Coupled with a new CEO who cut costs and increased profit at the expense of the workers (only to pocket a large sum for himself), a 6 month strike broke out and IH lost approximately $600 million (roughly $2 billion by todays standards). This was the beginning of the end for most of the company.
International Buses goods and services produce buses, chassis, and engines. Since the founding of the company, there have been some rough times in the International Bus history for sure, for example when they were removed from the S&P 500 and eventually the NYSE altogether. They have held on, produced many goods, and have been relisted on the NYSE, so they are reclaiming some lost ground. Despite the turmoil, International Buses, chassis, and International engines are well produced and a sound buy if you are looking for used International buses for sale.
Other engines produced by international buses: MaxxForce (5 - 4.5 Liter V-6, 7 - 6.4 Liter V-8, DT - 7.6 Liter I-6, 9 - 9.3L I-6, 10 - 9.3 Liter I-6, 11 - 11.0L I-6, 13 - 13.0L I-6), I6 (DT 466, HT 466, DT 530, HT 530, DT 466, HT 466, DT 530, HT 530, DT 570, HT 570).