In 1990, the 3680 was equipped with a Valmet engine, which is 10 hp more powerful than the 3690. At the same time, the 3670 model was available with a 6.6-liter (170 hp) Valmet engine. In 1992, as with the more compact models, the transmission was replaced by a four-speed Dynashift transmission. In 1994, the 3690 engine was upgraded to a newer model, the 634DS.

Interactive control support.