On Ḥol Ha-mo’ed, one may drive a car for the purpose of an outing, as anything that we generally do for fun and which is not demanding is considered a festival need. However, if the driving does not serve a festival need, it is prohibited. Therefore, one may not take driving lessons on Ḥol Ha-mo’ed, nor drive somewhere to check out something related to the work he will do after the festival.
Traveling via buses, trains, or taxis is permissible, as is paying for the trips. It is also permitted for Jewish drivers in Israel to work for pay on buses and trains on Ḥol Ha-mo’ed, since it serves the needs of the community. It is proper for cab drivers to take off from work. However, if the public needs them to work they may do so. In ḥutz la-aretz, a Jewish driver should make every effort to avoid driving professionally on Ḥol Ha-mo’ed; only if there is concern that he will lose his job may he work, as is it considered davar ha-aved.
One who needs to travel on the festival may do minor, unskilled auto repairs to enable this. Similarly, in the past when people traveled by horse, the Sages allowed people to engage in unskilled care of their horses, such as fixing their hooves on Ḥol Ha-mo’ed (MK 10a; SA 536:1). Therefore, it is permissible when necessary to change a tire, or to make small repairs that do not require specialized tools or professional expertise. In contrast, professional repairs may be undertaken only to prevent loss (as explained below in 12:2).
A car’s windshield and rear windows may be washed. However, a car may not be washed, as doing maintenance work on Ḥol Ha-mo’ed that is generally only undertaken once every few weeks is belittling Ḥol Ha-mo’ed. Nevertheless, if a Ḥol Ha-mo’ed trip made the car so filthy that it is embarrassing to drive it, one may wash the car so that it can continue to be used.
It would seem that the permissibility of outings on Ḥol Ha-mo’ed is limited to trips that are relatively short and not exhausting or demanding. Rather, they should be consistent with the goals of Ḥol Ha-mo’ed – to rest and to enjoy good meals and Torah study. We have already seen (1:6 and 10:6) that half the day should be dedicated to Torah study. Only half the day is left for trips, during which one should make sure to have meals as well. Nevertheless, it would seem that one may travel even a great distance in order to visit the holy city of Jerusalem, home of the Temple.