Let me start off by saying I drove 8 hours from New York to drop off my cylinder head core, and pickup my new head from these guys. Hands down the friendliest and most knowledgeable Cummins machine shop you’ll find anywhere period. I had no idea how bad my cylinder head was, I had a mysterious ticking that would only happen when the engine was warm around 1900rpm. After installing this head the truck sounds and runs like it’s brand new. I have compound turbos and 100% over injectors and with the new head and beefy pushrods and valve springs from D&J the truck feels like it gained hp from the head alone. I’m very impressed with the craftsmanship that went into this cylinder head, the packaging everything. If you need a cylinder head look no further! Dont waste your time with a local machine shops that have no experience with Cummins.

Purchase the stage 2 head, billet timing cover and freeze plugs. All was built beyond my greatest expectations!! Thank you so much drew for the great workmanship and the time to help me out with every question I had!!! Would recommended d&j to everyone..

Besides Bethlehem, the Lord picked a spot to put on earth known as D&J Precision Machine, Cambridge OH

Great, professional group. Shop was clean, work is top notch.Thanks

Awesome shop with great guys!

My experience with these guys is less than stellar, they made pistons that were 15 thousandths less than my bore and were told what the final bore was and they said the pistons were made too fit. This is what caused my motor to fail at 100 miles, look elsewhere for reputable shop! Drew is about excuses and if you do not mind throwing your money away then by all means deal with that disreputable horses butt!!!!

Not a good experience

Great guys with awesome products

Great place to deal with!