In recent years the construction of horizontally drilled wells has become commonplace. The horizontal sections of these wells have continued to increase in length as equipment and methods used in constructing these wells have improved. As lateral lengths have increased, so have the challenges associated with drilling and completing these wells. The high TMD/TVD ratios seen in many wells often presents challenges during the installation of casing and liners. The primary issue is the friction associated with horizontal well profiles and the absence of adequate vertical casing weight. In order to combat the problems associated with getting casing/liners to bottom, operators are increasingly using downhole vibratory tools to aid these operations. Vibratory downhole tools primarily help by breaking the static friction between the workstring and wellbore or casing. These tools are commonly used in horizontal well drilling operations but more recently these tools have also begun to be run on casing strings with great success. In this paper, the results of field tests using a downhole vibratory casing tool on a group of wells in the Niobrara and Codell formations are presented. Eight (8) wells were considered during the study. A vibratory casing tool was run in four (4) wells. Casing was run in four (4) additional wells in which no vibratory tool was used. The wells involved in the testing were completed with 4-1/2″ 13.5# P-110 liner in 2-section laterals. Evaluation of the data shows a 121% average increase in running speed while rotating the liner in the hole when using the vibratory casing tool, resulting in an average of a 23 hour (55%) decrease of rig time per run. Additionally, less torque at higher rotary speeds was seen on the wells in which the vibratory tool was run. The associated physics, operating methodology and effectiveness of these tools will also be presented.