Abstract
A great amount of engineering and development work is under way at the present time on the important subject of tire traction especially under wet surface conditions. Typical facilities used in the industry for traction testing of tires are described. Test to date have shown that by far the most important variables affecting tire reaction are: 1. speed, 2) the road surface, 3) weather conditions as they affect the road surface, 4) the conditions of the tire, particularly whether it is new or worn to the thread wear indicators.