What was the price of gas in 1948?

A gallon of gas cost 15 cents in 1944. It was only 35 cents in 1970 which means, adjusted for inflation, it was cheaper than in 1944.

Also the price in 1944 was kept fixed by wartime price controls since the beginning of the war and very heavily rationed. If people needed to do any extensive traveling by car in 1944 they picked up as many hitchhikers as they could and if the hitchhikers had any gas ration coupons in their ration books the driver made use of them too.