clay with truck on lift

Big Timber’s best diesel and gas engine repair and service

The mechanics at CMC Diesel are experienced and qualified to perform services and repairs on all diesel and gas engines.  With over 20 years experience, you can count on CMC Diesel to get the job done right, with excellent service that you can trust. 

Don’t just take our word for it- see these reviews from our customers:


Very Professional and outstanding… Read more “Outstanding!”

Lydie Pool

The CMC Diesel Staff and Mechanics:

Clay Cowell, Owner

Clay manages the shop, supervises the mechanics, and does full automotive repairs.  He obtained his bachelors degree in diesel mechanics from MSU Northern before moving to Big Timber and starting CMC Diesel.  He has over twenty years experience repairing diesel and gas engines, including boat, motorhome, and van engines.    

Melissa Cowell, Office Manager

Melissa manages the office, including scheduling, payments, and all record keeping.  Call her to schedule an appointment: 406.932.5021.  

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