Parnelli Jones took his only Indy 500 win despite his car (nicknamed "Calhoun") spewing oil from a cracked overflow tank for many laps, which allegedly caused at least one driver to spin and crash. USAC officials put off black-flagging Jones after car owner J. C. Agajanian ran down pit lane and convinced them that the oil leak was below the level of a known crack and would not leak any further.Lotus owner Colin Chapman, whose English-built, rear-engined Lotus-Ford finished second in the hands of Scotsman Jim Clark, accused USAC officials of being biased towards the American driver and car.

The non-black flagging of Jones remains controversial. Many, including Chapman and journalist and author Brock Yates, believed that had it been an American driver and car in second place instead of Clark in the British built Lotus, officials would have black flagged him.

Goodyear arrived at the track and supplied tires for some entries, but participated only in practice. No cars used Goodyear tires during time trials or the race itself. It was the first time since about 1921 that Goodyear attempted to compete at Indy. Goodyear had last won the race in 1919.

Time trials was scheduled for four days.

Parnelli Jones started from the pole position, and at the start, led the field into turn one. A fierce duel broke out in the opening laps. Jim Hurtubise, who started in the middle of the front row, caught up to Jones down the backstretch, and passed him for the lead. Hurtubise led at the stripe at the completion of lap 1. On lap 2, Jones caught up to Hurtubise again, and took the lead back in turn four, and led lap 2. Hurtubise dove down to re-take the lead in turn one, but Jones was able to slip by and hold the position.

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