Jeep Wrangler driving off-road with a 4BT Cummins engine
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Reviews and Testimonials

There's more engine builders throughout the United states that specialize in the 4bt than I ever would have thought. I've been in search for a replacement 4bt long block for the last few months. Contacted 3 in my home state of Michigan who more than wanted to sell me a Cummins 4b but they did seam to want to take the time to make sure I was going to get exactly what I needed, which was 3.9 4b Cummins for my Case w11b.

That's not the way Big Bear Engines operates, I now know everything I need to know about my 4b because big bear truly takes care of every single customer from start to finish and follow up. If you buy a 4bt long block any where else your not getting the best product available. When my engine arrived on time extremely well packaged; the $450 I paid in shipping to buy from big bear was worth every penny. 100% satisfaction.. Their knowledge of these engines guarantees you will be buying exactly what you need. Their goal is to get you the right engine not just to sell you one. Lifetime customer for all my 4bt engine needs.

Chad Bean, JR Automation: Holland, MI

I am doing my first rebuild on my 4bt Cummins so obviously there's a lot to learn. First and foremost should I go OEM or aftermarket? OEM is triple the price and I was wondering am I just buying the name or are the parts actually higher? Searching the web there are hundreds of overhaul kits to choose from there I stumbled upon big bear engines so I gave them a call. I first spoke to John who could not have been more helpful! He patiently answered all of my questions and I immediately sensed I chose the right place.

John in turn connected me with Mike who was helpful beyond belief! Now mind you I'm only buying an overhaul kit for around $ 500; not a big sale. Mike offered me so much helpful information. They obviously have a vast in-depth knowledge of engine rebuilding which they actually shared with me. They even called me one day out of the blue to explain the process to me! In addition to over the phone conversation they also sent me articles about aftermarket vs OEM. Now that I have the new engine I have been reading literature on how to break it in.

Even though I watched countless videos and researched, mike taught me things that I did not know.. the guy actually cares! I am amazed and thrilled I was lucky enough to have been able to deal with this company. It's a little intimidating doing your first rebuild but I feel a helluva lot better after my experience with this group of stand up helpful caring guys! I can not say enough good things about them. I would highly recommend them! thank you Big Bear sincerely George Westlund Brick New Jersey.

George Westlund, Brick, NJ

Delivery man said that was the best/coolest crate he's ever seen in all his years of delivery. Please see attached pic. The new engine looks great! Thanks again for all of your help. Happy New Year!

Clay McAlpine 4BT Engine Crate

Clay McAlpine, McAlpine Ranch, Valier, MT

John has been very helpful in providing us with 4bt engines and parts we need to repair old ones. Highly recommended this company!

Moises Fabela, Abatti Companies: El Centro, CA


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