I went there with a complaint of bucking or lurching at speeds between 35-55 mph. They hooked my engine up to their computer and said there were no codes and nothing was wrong with the engine. They wanted me to go to the local Allison shop for evaluation, but I told them I had already done that at an Allison shop in Albany, GA and the report showed no transmission problems. Finally I did go to the Allison shop in Tampa and they were able to retrieve the computer file from the Allison system and agreed the transmission was OK. They could see the bucking on the computer graph, but said all transmission sensors were in unison, so it could not be the transmission. The Cummins shop charged me $180 for hooking up my engine to their computer. I asked for an adjustment due to the fact that they did not find or solve my problem. The shop manager was defensive and refused to make an adjustment. He did agree to go on an extended test ride with me. The problem manifested several times, but he had no idea what was wrong. He said he was going to send the computer file to the engineers at Cummins, but never did. I went there with a specific problem. They charged me $180 but did not diagnose or solve my problem. It was later diagnosed and repaired by Cummins Power South in Atlanta.