Read What Our Customers Have To Say!

G&J Diesel were very professional and knowledgeable from the first phone call. I had read an article about 6.7 powerstroke fuel pump failures and that there was a fix for it, I called G & J Diesel Sales & Service, Inc. for their advice on the article I read. They confirmed that a failure of the pump would cause thousands of dollars of damage to my engine and that they have the kit that will stop the failed components from entering the fuel rails and injectors. Got an appointment for the next week and it was done by noon. My engine was clean no leaks and I was very impressed with the everyone there. I will definitely be back, great company

I took my truck to G & J after having a bad experience elsewhere. In the few days that they had the truck, they not only fixed the issues, but they were informative and kept me in the loop all the time. Even on the smallest of repairs, they did not perform any work until they received my approval. G & J is a great company to do business with and I highly recommend them. Furthermore, as a first-time diesel owner, I was unsure of some of the operations of the truck. Brad, the owner, took time on a Saturday, when they were closed, to drive the truck with me and answer all of my questions. My experience here was excellent and I will recommend them from now on.

What I like about G & J, is that they are up front and honest. If they feel repairs need to be done after the diag is completed in order to save a vehicle from no longer running, they give an honest to god estimate. It might not be what you want to hear, but it at least gives you an idea of where to begin. Their diagnostic/ mechanic team is fantastic and all of the office employees hands down know their stuff. I would recommend G & J to anyone with a diesel!

Great service and helpful friendly staff. Did not try to hide anything and were upfront about the repairs. Sam was great and provided excellent customer service.

The service is amazing I never have any problems when I go to G&J Diesel. I would recommend it to a lot of people. I've been going here for over 10 years.

Great place good people. Reasonable priced just did an oil pump for me in one day thank you guys.

Had my block machined there. Good service and reasonable rates.

Fast, Knowledgeable, professional, and honest. They even called days later to make sure we were satisfied.

Great communication and attention to detail. Thanks G&J!

I should have reviewed sooner. G&J was recommended by a co-worker who is a fantastic diesel and heavy equipment mechanic. Maverick (my 02 5.9 HO) runs better every visit. G&J has adjusted the timing, replaced wheel seals, replaced brakes, installed shocks, and installed a beautifully crafted MBRP Quiet tone exhaust.

Sam is friendly and thourough. G&J will be my go to on my way to 1 million miles (220k now)

G&J has earned an excellent reputation in the area. I needed a laundry list of items looked at on my 2nd gen Cummins and they did a great job confirming and remedying some serious issues, like the lift pump delivering dangerously low PSI to the injector pump. Diagnostics are not free here, but I appreciate that I'm more likely to get honest professional opinions and suggestions without the bottom line conflict of interest that drives some shady behavior in the industry. I'll be back for sure!

I'm a delivery driver for a intrastate courier, and I pickup and deliver many packages for G&J. The staff is always super friendly and very professional how they handle the calls and personal exchange in person. I absolutely love seeing them in the mornings when they have packages needing to go out to their customers. The customers always have good things to say about G&J.

G&J Diesel repair treated me great and went up and above to get my rig rolling again..Highly recommend. Two thumbs up!

Very friendly and professional service. The crew was sensitive to my needs and got my vehicle repaired in a very timely manner. Would definitely recommend G&J to friends.

They were a big help. Wouldn't go anywhere else in Billings.

Had a wonderful experience with these folks and would recommend them highly for diesel mechanic work.

I have used G&J on multiple occasions. Top notch service every time.

Amazing place to do business!!!! Always professional help. Been 12 years going in and will be many many more.

Awesome friendly staff.these people know what they are speaking about.good location.nice atmosphere. Knowledgeable staff..

Great experience. Called for an exhaust and told me it was in stock. Showed up a day later, they remembered who I was and grabbed the exhaust. They made sure it was the correct one even before taking my money. As we waited for them to load the box for us, they gave my son a ton of cool race stickers for his go-kart. Will definitely be back for my cold air intake.

Brad and the guys and gals at G&J have always performed above what's expected and usually found at the other shops who claim to work on diesel trucks. They have performed my repairs and maintenance for several trucks now and have done a great job. I had to take one 7.3 Ford to another shop and they even fixed all the mistakes from that shops "certified" techs work now. Lesson learned, wait your turn at G&J and get it repaired right.

Called in cause I needed some front end work done and I needed it done by today. They are hard at work so I can get back home. They call with check ups and even helped me out when another towing company was taking my truck. These individuals are amazing and I will do further business with them in the future.

Very knowledgeable and excellent service! Expensive!!! But, honestly I felt I got exactly what I paid for. Absolute quality. These guys bent over backwards for me. I ran into problems thousands of miles from home, on vacation. They took a fairly stressful situation and cured it in a timely manner. Thank you to all of the staff.

They did an awesome job for me! My 2015 diesel Grand Cherokee runs like a TOP & is getting well over 30mpg on the highway!! I totally recommend G & J Diesel!

Chevy crapped the bed on my way home from Cooke city to Michigan and they had the parts I needed IN STOCK and great customer service. Thanks guys!!

Very fast service replacing my F-350 GPR and doing diagnostics on the 4WD auto system - very satisfied and will go back for any future truck issues!

Fast and friendly service. professional and knowledgeable, would surely recommend. They were fast to respond to my questions and needs. Phone was answered on the first call.

They try very hard to help and advise. They listen carefully to your problems and try to solve them

I used G & J to order my air dog because I don't have any dealers near me and they were very fast and professional about it. They specialized in fass systems but ordered me an air dog and shipped it straight to my house without trying to force me into a fass. Thanks a bunch guys!

Great work on the old Dodge!!!

We broke down in Billings and they were very accommodating. They got us in as quickly as possible and they worked hard to get us back on the road. They were very friendly and informative. We felt that they were very fair and did a great job.