Welcome to Carlsen Sinclair & Service! For over 70 years, we have provided Montana with gas services and quality repairs. We pride ourselves in the quality of our products as well as our excellent customer service. In addition to providing our customers with the highest quality Sinclair gasoline, we have introduced a full service auto repair shop. Our highly trained technicians are happy to assist you with any of your mechanical fixes including; engine replacement, transmission repairs,routine maintenance and much more. Come in to Carlsen Sinclair & Service today. We are happy to assist you!