Changing Places by David Lodge

When Philip Swallow and Professor Morris Zapp participate in their universities' Anglo-American exchange scheme, the Fates play a hand, and each academic finds himself enmeshed in the life of his counterpart on the opposite side of the Atlantic.

Nobody is immune to the exchange: students, colleagues, even wives are swapped as events spiral out of control. And soon both sundrenched Euphoric State university and rain-kissed university of Rummidge are a hotbed of intrigue, lawlessness and broken vows...