You can and read and watch the highlights of his Congressional testimony HERE.
But why does Toyoda, the grandson of the Company's founder, spell with a "d" and not a "t"?
BTW: Akio's grandfather, Kiichiro Toyoda the founder of the company pictured here, also spelled his last name with a "d".
1) It sounds better and
2) It takes exactly eight brushstrokes to write "Toyota" in katakana, one of the two phonetic alphabets in Japanese whle "Toyoda" requires 10.
According to the Washington Post:
"Eight, widely known as a lucky number in China, is also fortuitous in Japan. Its luck stems from the way "eight" is written two strokes side by side, placed so that the character resembles an open mountain top. For the Japanese, the wider base symbolizes growth and prosperity in the future, which is exactly what Toyoda hoped for both his company and country.
The spelling tweak also served as a symbolic break from Japan's agricultural past. "Toyoda" literally means "fertile rice fields." Toyota the company, however, sought success through innovation and manufacturing prowess."