A reader heard a rumor that the winner of the 1972 Pike’s Peak “in the unlimited class was a cj3a”. I found a video of the 1972 race, but no jeep was mentioned:

I also learned that the overall winner on one day of the 1971 Pikes Peak Hill Climb trials was Bob Sievert (his obit) in a jeep, but Bob failed to win that year. His rear end broke during his race up the hill, forcing him to rely on his front wheel drive. Still, he finished 5th in the four-wheel-drive class. Here are the results of that 1971 race, though no pics are provided that show why type of jeeps were raced:

Colorado Springs Gazette-Telegraph, July 12, 1971.

In 1973, Bob did win the Non-Production Truck division of the Pikes Peak race. There’s supposed to be a mention about him and his jeep in the July 1973 issue of Hot Rod Magazine. Eventually, I was able to find a photo of Bob from 1973, but it appears he raced using a modified Jeepster Commando:

https://www.pinterest.ie/pin/516928863464329770/

There was another jeep entry in 1973, this CJ-5 operated by Ken Anderson, but no mention of how well he did:

So, I’ve been unable to confirm that a CJ-3A was used or modified for the Pikes Peak Hill Climb, but I’m sure CJ-3As, as well as WWII jeeps and CJ-2As and other vintage jeeps were raced given there was a 4WD class. Anyone else have more info or photos?