Toyota announced today that it will spend $373 million on a deal with Isuzu that will transfer 5.9% of the truck- and diesel-maker to the giant Japanese automaker. Toyota's goal in purchasing a stake in Isuzu is to bolster its diesel portfolio, which apparently lags behind other major automakers like cross-town rival Honda who announced in September it would have diesel-powered passenger cars for sale in the U.S. within three years.